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The hornet's nest resurrection project
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Beartooth  



Joined: 05 Apr 2022
Posts: 198
Location: Roberts, MT

PostPosted: Wed Apr 13, 2022 5:25 pm    Post subject: The hornet's nest resurrection project Reply with quote

Guess I should introduce myself. I'm a pilot and life-long gearhead. I cut my teeth on an old Ford Fairlane (which I still own), then branched out into Mercedes (mostly W126s, but I've also got a 300D flip project), and snowmobiles. Lived all over the country and saw a lot of the world in the military, and have been working in the reserves and building a house the last five years. Anyway, I'd read a little about the 924 and 944 over the years, but never thought of buying one until I stumbled across this one. If anything, the 928 was the Porsche that thought the most of actually buying. What I found is a 1980 924 Turbo, and I managed to find one with the four-lug wheels and drum brakes, so, lucky me!

Anyway, I thought about calling it the rat's nest; fortunately, I haven't found any evidence of rats. But there are dozens of dead hornets on the dash, so there you go! I rolled the dice on this car: the price was right even if I have to part it or pass it on to somebody else. I got very little history except for "ran when parked because of slave cylinder problems." The gas in it would have been rejected by the most desperate arsonist, and it had a pile of tree leaves and needles (why do people park derelict vehicles under trees? And did somebody get it going just long enough to move it from under pine trees to cottonwoods, or did it get moved around in its lifeless state?). The main fuel filter was loose, and (I later came to find out) backwards, and there was a can of starter fluid under the hood. The tires somehow hold air, but are nearly bald and cracking. So, this thing has been sitting a loooong time. But, on the plus side, it's totally complete as far as I can tell. Other than some chintzy fog lamps, a few foreign wires running here and there, and some cheap bungee straps holding the air cleaner housing together, it doesn't show much sign of having been subjected to hack-job mechanicking. It's got a ding in the left fender and another on the right quarter panel (guess it balances out), but other than that, it's an entirely straight and rust-free car. Honestly, if it doesn't work out, I'd probably just part out the mechanicals. I couldn't bear to scrap it: I know I'd eventually find a good runner in need of a straight body, or someone looking for the same.

Anyway, here's what I've done so far. I pressure washed the body and as much of the undercarriage as I could reach, as well as washing down the engine bay (not with the pressure washer). I drained the fuel tank, which was an awful job. I also flushed the fuel lines with brake cleaner and compressed air. Once I got it inside, I took the fuel distributor off (the plunger was frozen), and have been able to take that apart, free the plunger, and clean all the gunk out of it. Cleaned up, it looks like new. The o-rings and all weren't solidified, as you'd expect if it were original, so that may have been replaced or rebuilt at some point. I'm working on getting to the warm-up regulator, hopefully I can make that serviceable too. The injectors probably need to be replaced, but just pouring a little Sea-Foam in and blowing it through with compressed air, they seem to spray well enough to run, and it doesn't look like I have any dribblers. I also pulled the spark plugs, WR6DPs, which would seem doubly incorrect, being colder than specified and platinums, which tend to weaken the spark. They looked ok except for #4 being fairly dark; maybe a bad injector or fuel distributor issue.

About all I could verify before I bought the car was that it'd turn over freely. Given the possibility of major mechanical issues that'd make it too expensive to continue, I'm just working methodically to see if I can get it running first, then get the clutch working and move on from there. To that end, I'm going to replace the timing belt and change the oil to start (the oil smells a little like the gas, and it'd probably be garbage anyway), clean up the rest of the fuel lines, replace the fuel filter (and probably eliminate the in-tank pump, at least temporarily, so I can run a big, transparent prefilter to catch whatever else is in that gas tank), and just see where that takes me. I'll probably do a compression test too.

So far I've resisted the urge to buy several boxes of new parts. I'm trying to keep it fairly low-dollar (and I know, I bought the wrong car), and will work with used parts and rebuilding things myself where I can. With that in mind, what other things would be wise to do before trying to get it running? Obviously, fuel delivery and the injection system are the biggest thing to sort out. I'm thinking I'll squirt a little oil in the cylinders and crank it with the plugs out, after I change the oil, just so the rings aren't dry. Any thoughts on things to clean out the crank-case? I've heard it suggested to add some ATF or Sea-Foam (among other things) to the oil and run it a half hour or so, then change it out. Worth doing, or just inviting trouble? I'm just going to put some cheap oil in and change it out pretty quickly either way. Hopefully the clutch issue is just the hydraulics. The brake reservoir is low, and I noticed an apparent leak from the left rear brake, so it could just have got air in it (pedal snaps to the floor at the moment). I suppose I should dig into that sooner rather than later, since it'll hold everything else up once I get it running.

Things I know I'll need to address if I can get it into a driveable state include: pretty much all the fuel, cooling, and air/vacuum hoses. They look original to the car, and I'm sure gas-fueled fires are as common a killer on these as my Mercedes (never had a fire - knock on wood - learned from others' mistakes, so if I smell gas, I find it and fix it). Pretty much all rubber parts in the suspension and such will need attention, I'm sure, and things like brakes, shocks, etc. Then, there's lots of dry rot on the cabin seals; I might look into using universal stuff, but it probably won't be a big priority since this will be more of a nice weather car. Oh, and the upholstery is pretty bad. Bad enough that I'll have to do something if I expect any less adventurous types to want to ride in it. I think the carpets and such will clean up well enough, and it doesn't have any bad smells, but the seats are cracked open with exposed foam. Would be a good place to go junk yard shopping, but I probably own one of three or so 924s in the entire state.

Ultimately, the ratty nature of the car isn't a big deterrent to me because I'm mostly looking for something fun to go back-roads blasting, and that mostly means gravel around here. I'd love to go whole hog and repaint it, do a proper interior restoration, swap to five-lugs and all disks, and of course cranking up the HP - the whole nine yards. But I'm trying to keep the budget reasonable, and I think it'll be plenty of fun if I can just get it going as-is. I may end up doing a number of DIY, non-purist-friendly fix-ups just to make it fully functional and presentable; it'll never win any points for originality, but hopefully I can make it turn heads (in a good way) again. And maybe that's what I like about a car like the 924 over a 911: it's a car you can do on a budget, do it your way, and as long as you have some clue what you're doing and don't get too hair-brained, you'll have something cool and unique. You may never make money on the deal, but then nobody can complain that you killed $20,000 in resale because you painted the wheels or something.
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morghen  



Joined: 21 Jan 2005
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Location: Romania

PostPosted: Wed Apr 13, 2022 5:58 pm    Post subject: Reply with quote

Welcome to the board.
DONT turn the motor before you put a fresh belt on it and properly set the engine timing, you will bend the very expensive and rare to find valves if the belt snaps or jumps.

Keep the posts coming and learn to link pictures to your posts.
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peterld  



Joined: 10 Dec 2006
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Location: Noosa Heads QLD Australia

PostPosted: Wed Apr 13, 2022 10:59 pm    Post subject: Reply with quote

Welcome aBoard!

You have your order of priorities about right. But as Morghen says.......timing belt and timing are critical, and cheap and easy to do.

Pull the clutch slave cylinder, and if the bore is OK then a simple rebuild kit (rubber and circlips) will fix. Whatever rubber is used in these slaves is regularly problematic.

Seats can be sourced from early 944 (as well as the tasty five lugs)

Best of luck in saving another one.
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Last edited by peterld on Fri Apr 22, 2022 9:43 pm; edited 1 time in total
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Fifty50Plus  



Joined: 28 Feb 2008
Posts: 1353
Location: Washington DC area

PostPosted: Wed Apr 13, 2022 11:35 pm    Post subject: Reply with quote

Welcome aboard. It sounds like you have a systematic approach to reviving your car although it sounds fairly neglected. TIMING BELT first.
There is a member here (Gatornapper) that has taken on the restoration of his turbo over the past year and has done quite a bit of documentation on the process. It's a very good read and could act as a script for you to follow as you discover issues and renew your car.
One word of advice - almost every newbie here initially talks about hopping up his engine even before he gets it running. Forget that. Increased performance is costly and requires that everything is in good working order first. Get your car running well and fix things incrementally as you begin to enjoy it.
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1979 924 NA race car
1982 924 NA race car - Sold
1982 924 Turbo almost a PoS
1981 924 Turbo a real PoS, new engine
1982 924 Turbo nice body, blown engine
1972 911 E race car - going to Vintage
Various 944s to become IT-S race car
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Beartooth  



Joined: 05 Apr 2022
Posts: 198
Location: Roberts, MT

PostPosted: Thu Apr 14, 2022 4:51 am    Post subject: Reply with quote

Thanks for all the input! I've got some pics to add, just got to get them uploaded. I will definitely replace the timing belt before I turn the motor over again. The more I read, the more I realize how much OE parts, especially engine/transmission internals, are becoming unobtanium. I wish the aftermarket was more geared up for small batches to meet demand from smaller communities; at least that's getting better. The aftermarket (in the US anyway) is still growing out of the model where you went into the business building parts for 350 Chevies, made huge runs of parts, and rarely expanded outside the big three. But that's neither here nor there.

Anyway, I've been digging through, and found a lot of good info already. I've seen a few of Gatornapper's posts. It definitely helps having resources like this; I can't imagine what it would have been like 30 years ago trying to restore an old Porsche, although at least then, when you found parts you had much less chance of them being garbage from China. Speaking of, what's a good source for rubber pieces for the clutch hydraulics and brakes? I'm having a hard time finding anything listed for the clutch master/slave or brake calipers. It's not a priority until I get it moving on its own power, and I wouldn't take it any further than a slow lap around the neighborhood without addressing all that, but hopefully I'll get to that point sooner or later.

20-ish years ago, when I bought my first car, I was one of those guys who'd have been asking "how much more power can I get out of this?" when I should have been asking "how do I get this thing to run right and not break it trying?" It being a turbo, and me being the type who'd always like a little more power, I've got thoughts of intercooling, water/meth injection, and such. But I know that's way down the road! The way I think of it now, I can pick up at least a hundred HP, and probably another thirty on top of that. I'm sitting on zero right now (well, .2 if I push it), so I pick up a ton of power just getting it running, and more yet getting it back in tune! Hopefully the cheapest HP I'll get...
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Fasteddie313  



Joined: 29 Sep 2013
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PostPosted: Thu Apr 14, 2022 5:20 am    Post subject: Reply with quote



Welcome welcome!!

I’d change the timing belt and tensioner, maybe a new distributor cap and rotor..
That should cost you a whole $40..

Then see if it’ll run on starting fluid a bit..

But a Haynes manual.. Buy/make a CIS pressure tester..

In the Haynes manual you will find the protocol to perform an injector flow test..

Put about 5 gallons of fresh gasoline in it and 2 full bottles of TECHRON injector cleaner.. Techron..

Run the injector flow test into your bottles, A LOT, just as a way of flushing your system and letting that Techron go to work!
Pushing the plate up and down varying the flow and working the system.. Exercise it..
Let it sit for a day, and do it again the next day..
If the gas coming out of your injectors doesn’t look too bad, but it back in your tank, and keep exercising it doing the injector flow test (basically running the entire fuel system)..

Do that a bunch before deciding any of it is junk..

If any of it IS junk after all that, let me know, I have spares of most of it to ship you..


Good luck and have FUN!!
This is one of the best choices of cars IMO for tinkering and doing truly CUSTOM work on.. I love it!


"how much more power can I get out of this?"
Ohhh..
It can be made a bit of a handful requiring caution without much $$ if you have some skills and ambition for tinkering..
It’s surely not without much future potential..


Clutch master/slave are cheap/easy to get.. Think like $140 on eBay for both..

https://www.ebay.com/itm/151214445523?fits=Model%3A924%7CMake%3APorsche&hash=item23351553d3:g:bGMAAOSwI-hZ1JjW

ATF in the crankcase? Yep..
I’ve done it to many engines and would do it to this one..



“pick up a ton of power just getting it running, and more yet getting it back in tune! Hopefully the cheapest HP I'll get...”
Maybe..
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Beartooth  



Joined: 05 Apr 2022
Posts: 198
Location: Roberts, MT

PostPosted: Fri Apr 22, 2022 5:06 pm    Post subject: Reply with quote

So, fairly steady progress, and no big problems so far. I pulled the valve cover off, and everything looks good up top. I poured some oil on the cam and smeared on some assembly lube for good measure. I also used my borescope to have a look at the pistons. The only sign of trouble (other than a shiny piece of debris that I thought was a nick in a piston) was some scratches on the #1 piston. Probably somebody was using a screwdriver to find TDC, but definitely doesn't look like it happened with the engine running. I'm getting close to done with the fuel system. I took the warm-up regulator off, cleaned it up, and checked it out. Seems solid and the diaphragm is fine. I may need a new fuel pump, but I don't think the existing one is burnt out. I can hear a bit of a click when I hot-wire it, and it may just be gummed up and frozen. I've been soaking it in gas and fuel system cleaner, and I think the gunk is starting to break up, but I still can't get more than a click out of it.

So far I've accumulated a new fuel and oil filter, timing belt and tensioner, and a set of spark plugs. I managed to find a set of WR6DS plugs off Rock Auto, which is lucky since I don't think they're made anymore. I'm guessing it's similar to the situation with the factory specified non-resistor plugs in my Mercedes: it's cheaper to make them all the same, so they claim the closest thing is just as good (at least the WR7DC doesn't run the danger of burning out ignition components, unlike resistor plugs in the Merc). I'm not sure about the heat range, because the sticker under the hood says WR7DS, but apparently the newer turbos got WR6s from the factory? At last the colder plug won't hurt anything.

Anyway, I changed the oil today. There was a little water that came out with it, just a few ounces though. On a whim, I poured a little gas through the oil drain in the head, then chased it with some fresh oil. Hopefully that helped flush some of the nastiness out. Other little bits and pieces: I sucked the brake fluid out of the lines as much as possible (using a mity-vac vacuum bleeder setup) and took the master cylinder off. I intend to pull the booster to give more access to the clutch master cylinder. I poured around 5ml of oil down the injector ports, then turned the engine over by hand a few times to hopefully get some lubrication on the rings and cylinder walls. Once I get the timing belt and tensioner changed, I'll start cranking it over to do a compression test, and hopefully get the fresh oil circulated before I try to fire it up.

In terms of getting it running, hopefully I can get the fuel pump to work. If not, that would probably be the next part to buy. I see the parts section recommends the Pierburg pump; I'm curious as to whether that's worth the extra $50 over the Bosch 69458 universal pump (looks like either one should work, just may not come with the correct fittings). One thing I'm planning on doing is removing the in-tank pump and putting a universal filter between the thank and the pump. I could only find a 3/8" in/out filter, but I can get the 12mm hose to slip over a 1/2-3/8 adapter, so it should work. This isn't something I plan to keep (will probably buy the 944 fuel strainer), it's just something to catch the crud that's sure to come out of the tank with the first several gallons of gas. It shouldn't be an issue just running the engine lightly, but I'll take it out before I try to push anything (hopefully I get there). I suspect the in-tank pump really only comes into play if you're pushing hard and/or have a low tank. My Mercedes have no in-tank pumps, but the pumps are below the level of the gas tank. Pretty sure these pumps don't do well trying to suction; in this case, you'd only have suction with a pretty low tank, and even then, the in-tank pump may be as much to prevent damaging the main pump from suction as keeping the engine fed under boost.

I still haven't touched anything with the ignition. I've got some spiral-core plug wires and terminals sitting around, so I'll probably throw those on rater than trying to run the Autolite wires that are on it. Who knows if I'll get spark. The coil has about what I'd expect for primary and secondary resistance; not sure what else I can check passively. If that ends up being a problem, I'll probably just buy a the Pertronix setup for it unless I can find some parts for cheap. One step at a time though...
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jacobroufa  



Joined: 18 Nov 2016
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Location: Belvidere, IL

PostPosted: Fri Apr 22, 2022 10:25 pm    Post subject: Reply with quote

Sounds like a real sweet find and project!

While you've got the valve cover off, there's a cam oiling tube that runs the length of the head connected to its source by a plastic elbow that gets brittle and cracks often. The thing is cheap and worth changing if you have to open that valve cover..

Regarding the dual pump setup, I think everyone I know runs a single pump and strainer.. These old pumps put out massive pressure for our CIS and far as I have learned only one is needed.

I am not sure there is a pertronix setup for these cars -- they all came with electronic ignition already so the distributor can't be retrofit with e.g. a beetle distributor (which is the application of pertronix I am most familiar with). For an aftermarket ignition system there are a couple options: lots of folks seem to go with either the Ford EDIS or a late model VW coil, using a trigger wheel and something like Microsquirt to set it up. There's also the Mittelmotor distributor, which is a custom map on a 123ignition unit as far as I can tell, though (surprising to me anyhow) I don't know of anyone that has one of the latter.

---

Re: power mods as you mentioned there's lots else to do. These cars are amazingly capable in modern traffic for their age, in good tune. There's some nutty folks on the board here who have given them real modern power as well, so you're in good company.

I would recommend using e.g. imgur.com for posting images; you can upload for free and link many different sizes with the BBCode this board uses.
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Beartooth  



Joined: 05 Apr 2022
Posts: 198
Location: Roberts, MT

PostPosted: Sun May 15, 2022 3:28 pm    Post subject: Reply with quote

Sorry to be such a phantom! I've gotten distracted with a couple other projects, spent last week tearing into the rear suspension of my Mercedes. But that's another story. I finally gave up on the fuel pump and bought a new one. Soaking it in fuel system cleaner and trying to bump it back and forth off the battery. Not sure what was binding it up, but I spent more time on it than it was worth barking up that tree. I finally blew a fuse or something in it. It won't take current anymore; I think I let too much fluid out of it while I was trying to get it to run, I think there's a thermal fuse. So, if you're trying to resuscitate a pump, make sure you immerse it or fill it with something so you don't just burn it out. In my case, that something was gas... Not suggesting that, won't tell you it's safe, and it's definitely not the kind of thing you want to do in enclosed spaces or near sparks or flames...

Couple shots of the exterior.



Shot of the engine bay.


And the interior.


Hopefully I can get back after it this coming week. The other issue I'm waiting on is the title: it got lost during the derelict years, so I had to do a bunch of paperwork (with help from the seller) for a break title. Fortunately, being old enough and cheap enough, it doesn't have to be bonded.
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Beartooth  



Joined: 05 Apr 2022
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Location: Roberts, MT

PostPosted: Fri May 20, 2022 7:48 am    Post subject: Reply with quote

Compression test is done, and I'm going to start putting things back together. The results weren't perfect, but I think about as good as I could have expected. I found a formula for expected cranking compression. It's SP*CR*VE=CP (SP=static pressure; CR=compression ratio; VE=volumetric efficiency; CP=cranking pressure), and plugging in for my elevation and engine, I ended up with 12.4*7.5*1.15=107. I live at 4500', which equates to 12.4 psi atmospheric pressure, and the suggested value for VE was 1.15. I'd think the actual VE, at least as I'm familiar with the term, is much lower for these engines, but using 1.15 puts the expected numbers in more realistic territory. Anyway, the numbers I got ranged from 100 to 112 PSI.

I'm not sure what to make of the average figure, but the good news is that I don't have any cylinder too far out of range. Before I started cranking, BTW, I did get the new timing belt on, and a couple weeks ago I'd dribbled a half ounce or so of oil down the injector port and turned the motor over by hand several times to let that oil work down into the cylinders. So that may have "juiced" the figures a little (would help seal the intake valve and rings), but hopefully not too much, since it had a while to settle and seep down the cylinders. It might be interesting to see what the numbers look like after it's run and I've done an ATF oil flush and change. I do have a leakdown tester too, but it's recommended to use that on a warm motor, and I'm just looking for big problems at the moment. It's probably academic anyway: about the only use would be to tell me I've just got a leaky motor, in the event that it won't run right or burns a lot of oil.
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Fasteddie313  



Joined: 29 Sep 2013
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PostPosted: Fri May 20, 2022 10:59 am    Post subject: Reply with quote

Looks like a fine comp test to me..
Cylinder being very even is the most important IMO..
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Beartooth  



Joined: 05 Apr 2022
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Location: Roberts, MT

PostPosted: Mon Jun 06, 2022 5:34 am    Post subject: Reply with quote

I'm finally piecing things back together. I ended up taking the air flow box (what the fuel distributor attaches to) apart and cleaning it all out. Either there's a little fuel that seeps past the fuel distributor or the crankcase ventilation puts out a lot of crud, because it had a layer of brown crud. There was no plug in the hole for idle adjustment either; I decided to tap that, and I'll put a threaded plug in.

I also have the fuel supply all together and working. What I ended up doing, because I didn't want to risk having some sludge and crud getting pumped into the fuel distributor I just cleaned out, was to just hook the supply and return lines together so I could circulate fuel through the lines. I did that by taking a 12mm bolt and grinding a flat in the shank so I could bolt the two banjo fittings together. The area I ground out of the bolt matches where the two banjo fittings meet. Then I just put a crush washer between and on top and bottom and tightened it down. It doesn't leak a drop, and I can see good flow in the clear filter I put between the tank and pump. I've run it for a couple minutes two or three times, and figure I'll do it a couple more times before I hook it up.

In setting that up, I found something strange. The fuel pump relay is missing (unless it got put in a different slot). I was going to make a jumper wire, but there was a jumper wire in the socket for the relay already. It wasn't from battery to pump: one end was to the pump, and I think the other may have been to the switched power (which sounds like a bad idea). It seems the fuel pump relay is NLA. Is there a good substitute? Can you use a basic relay in its place? For the moment, I just need some way to power the pump, but obviously, I'd rather not try to run it with the pump hot-wired.
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jacobroufa  



Joined: 18 Nov 2016
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PostPosted: Mon Jun 06, 2022 12:09 pm    Post subject: Reply with quote

Fuel pump relay can be had at Pelican and elsewhere:
https://www.pelicanparts.com/More_Info/433906059.htm?pn=433-906-059-INT

Part number: 433 906 059
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Beartooth  



Joined: 05 Apr 2022
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Location: Roberts, MT

PostPosted: Sun Jun 12, 2022 9:41 am    Post subject: Reply with quote

Thanks for the tip on the relay, I'll have to order one. Had checked several other places and searched the interwebs for "924 fuel pump relay" without success...

So, I've now taken the clutch hydraulics apart as well as the brake master cylinder. The clutch hydros are kind of a PITA; wish the clutch master wasn't buried under the wiring harness, and that the slave wasn't up above the starter. At least removing the starter is pretty easy, and then you have room to work. Anyway, the rubbers in the clutch master and slave all looked pretty good, but there was some corrosion in both. The slave cylinder was worse. Still, none of it was particularly deep, so I improvised a hone using a piece of wood, some rubber tubing, and 180-grit sandpaper. I didn't want to wait for a ball hone set, and I heard they leave a fairly rough finish anyway.

I cleaned everything up and pieced it all back together. I also cleaned out and honed the master cylinder. There was a bit of corrosion in that too, and some of the seals look sketchy. So, pretty good chance I'll be looking for a master cylinder (and if anyone has a known good one...). It's probably not worth spending fairly big money on a new one, the catch-22 being that I won't know how badly I want to go to the better brake setup until I've had a chance to drive it some, and driving around with a questionable master cylinder isn't a great idea. I especially don't expect much from the current master cylinder now that I've got the clutch working... kinda... sorta. It does work, but if you don't step on the pedal like you mean it, it'll sag almost halfway before you get normal pressure, and then you have to pull it back up. Pretty sure I got all the air out, because if you stomp on it, you get normal engagement, and it comes back up like normal. Probably the seal needs some pressure to seat to the wall of the master cylinder; if it moves slowly, fluid can work past until it hits a good spot in the master cylinder.

I'll have to replace the master and slave at some point, once I get it driving, assuming I don't find any show-stoppers. Really, the reason I detoured to work on the hydraulics was in the hope that I could get it working well enough to move under its own power once I get the engine going. I dribbled some oil down the cylinders, and it's liable to chug and smoke anyway, so being able to pull it out of the garage (which is part of my basement) and back in again would be good. Hopefully that's coming soon: I just have to piece the intake and fuel injection back together, and I just got a nice crimping tool that does plug wires, so I'm going to rebuild some performance wires I have sitting around. Then I just have to hope the ignition feels up to waking up again.
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Beartooth  



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PostPosted: Mon Jun 27, 2022 3:24 pm    Post subject: Reply with quote

I've got the fuel injection back together, and approaching functionality, but I have a problem to get to the bottom of before I try to fire it. The good is that I seem to have the right fuel pressure (5.5 bar; in the range according to the Haynes manual) and the fuel distributor seems to be dispensing fuel evenly. Initially, I had no residual fuel pressure, but I went into the FD again and swapped some o-rings. Now it seems to hold. The injectors work well enough to get it running, I think, but will need to be replaced. Spray patterns are completely inconsistent, and a couple of them will dribble or stream sometimes at the start of fuel delivery. Now that I've sized the o-rings, I think I'll just order those (Viton seems to be the best option without getting exotic) and call it good on the FD since the diaphragm seems good. $20 instead of $75-120 for a full rebuild kit.

Anyway, the problem I'm having is the control pressure is way too high. I was at least seeing a little less pressure (like 4.5 bar) initially, but since the last go-around with the FD, it's almost the same as system pressure. The diaphragm is lined up correctly so the port between bottom and top is connected. I don't see any difference in clocking the barrel other than making sure the ports to the chambers are aligned, but let me know if I'm missing something there. I took the WUR apart again, and I can't find anything obviously amiss. This is all cold; I haven't tried hooking up the electrical element since that would only raise it... So I'm doing some reading on the WUR, and I'll tinker with that some more. It's weird because I can't find any blockages in the lines or WUR itself, the diaphragm is intact, and I'm pretty sure I'm putting it together right. Maybe the bi-metal arm is way out of whack? I might start by putting a couple washers under that and see what I get...
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