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Vaccum System and installing head
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MikeJinCO  



Joined: 08 Jun 2010
Posts: 704
Location: Maysville, Colorado

PostPosted: Fri Sep 09, 2011 1:23 am    Post subject: Vaccum System and installing head Reply with quote

While I've been concentrating on getting the suspension back together in a very modified format I've been ignoring the locked up motor that popped free yesterday after removing the head. Apparently there was a small water leak on the head gasket allowing a seep that sat for too long,corroded the cly. wall/rings and locked the pistons. I'll clean it up with some 1200 grit paper, minimal skim the head and try to refit it back together.

This all leads to two questions. Firstly what is the trick to getting the head gasket and head back on in the right location? Being at 45 degrees everything wants to slide around. Do I drop some locating pins in a couple of the head bolt holes or what?

Secondly I found the EGR system plugged at the exhaust pipe. I have no emissions requirements so see no reason not to remove the rest of the EGR system which makes much of the vacuum system not used. The website Applebit has shows to reduce the vacuum system to manifold to distributor and then from the retard side of distributor to the brake booster. Is this enough vacuum to the brake booster or would I be better off routing back thru the vacuum amplifier to the brake booster?

PS it is an ex CA car so I took off the air pump also. That is a lot of stuff out of the engine compartment.
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ideola  



Joined: 01 Oct 2004
Posts: 15489
Location: Woodstock IL

PostPosted: Fri Sep 09, 2011 1:41 am    Post subject: Reply with quote

Regarding the head install, there are supposed to be two locating sleeves that go into two of the head bolt blind holes on the block. If I recall correctly, you should see that the upper left and upper right head bolt threaded holes on the block (if you're standing on the exhaust side of the engine bay) are machined to accommodate the locating sleeves.

The part number for these locating sleeves (or "tensioning sleeves" as they're called in PET) is 046 103 139. Unfortunately, I believe these are NLA from Porsche. I used to include these in my complete engine rebuild kits, but about three months ago, my supplier told me they were now NLA. You might get lucky with one of the big resellers or local Porsche dealers who might have a spare set on the shelf (e.g. Pelican shows them as still being available, but a special order part...so don't hold your breath!). In the meantime, there is nothing magical about them. If you have the old pair, you can reuse them.

It would be interesting to see if we could find a VW or Audi equivalent...
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Fifty50Plus  



Joined: 28 Feb 2008
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Location: Washington DC area

PostPosted: Fri Sep 09, 2011 5:41 am    Post subject: Re: Vaccum System and installing head Reply with quote

MikeJinCO wrote:
Apparently there was a small water leak on the head gasket allowing a seep that sat for too long,corroded the cly. wall/rings and locked the pistons. I'll clean it up with some 1200 grit paper


I'd be quite leery of that as a fix - you might wind up with quite a loss of compression and subsequent blow-by.
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Joes924Racer  



Joined: 03 Nov 2002
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PostPosted: Fri Sep 09, 2011 6:07 am    Post subject: Reply with quote

by the phrase popped free ... to me that means it never ran and locked just sat and locked hot to knock your knowledge base and insult you..
that would be just wrong... do post a pic..As long as theres not imbedded particles and vertical groves along the cyl. wall . get a can of WD- 40 and give it a simple very light hand hone job & dont let those leary intrusions grow on you. Good - luck.
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MikeJinCO  



Joined: 08 Jun 2010
Posts: 704
Location: Maysville, Colorado

PostPosted: Fri Sep 09, 2011 1:58 pm    Post subject: Reply with quote

50plus-- I won't disagree with you, but I'm getting a '79 motor next month, bigger valves etc so I'm going to put more of my time and probably way too much money into that one. But at the rate I work on this it will be at least another year to get it done. Wintering in Mexico really slows down progress, but the snorkeling in the Yucatan is really nice and the Victoria beer is outstanding.

The motor sat from last October until July(see Mexico above) when I decided to roll it over to check the valve clearances. It wouldn't budge. I first tried to fill the combustion chambers with ATF, but with the motor at 45 degrees that doesn't work well. So I pulled the head and sprayed with PB Blaster several times and let it sit. Still not a budge. Then I popped the top of the pistons with the handle of a 3lb hammer and about 1 hour later the solvent had it broken loose. The head gasket does show some rusty water stains on the #4 cyl seal. Altogether not a great situation.

Joes It was running last September then I shut it off when the fuel dizzy started leaking(have a spare). I didn't want to run it until I got the fuel tank cleaned out which hasn't happened yet as it is still on jack stands getting the suspension finished up. Now, I won't be able to touch it again until about Oct 10 due to happenings around here.

Is Porsche the source for exhaust manifold studs? I have 2 missing/broken.

I guess for locating the head I'll try to find some cheap low grade 12mm(guess) bolts, cut the head off and weld on a smaller socket head cap screw that so I can slip the head and gasket over them and then pull the bolts back out. Metric all thread would be another possibility, maybe McMaster Carr?
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fiat22turbo  



Joined: 18 Jan 2006
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PostPosted: Fri Sep 09, 2011 4:17 pm    Post subject: Reply with quote

Head studs will fix the locating issue.

The locating sleeves are really only needed when mounting the head in the car, as long as you gently snug up the head bolts before tightening them down properly you should be fine. If you're doing it on the engine stand it isn't really an issue.

Exhaust studs just need to be metric and with a small-headed nut to clear the exhaust. The factory ones backed out on me, so I'm not impressed with them. The turbo cars use a special setup, but you don't need to worry about that.
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MikeJinCO  



Joined: 08 Jun 2010
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Location: Maysville, Colorado

PostPosted: Sat Sep 10, 2011 12:15 am    Post subject: Reply with quote

Poking around on the web I found techtonics tuning, the VW turners have 8mm studs for about $1.25 each. When I get back in Oct I'll try to pull one out and get the length and thread pitch as those might work.
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ideola  



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PostPosted: Sat Sep 10, 2011 12:40 am    Post subject: Reply with quote

In my experience, head studs do not fix the locating issue because there is still alot of slop around where the locating sleeves should go. When working on an engine stand, you could probably manually manipulate the assembly to get things lined up somewhat close but the gaskets I've installed don't always line up flush with the surfaces of the head/block. Trying to do this with the engine in situ would be challenging, although not impossible. It's not an insurmountable issue, but I think it's much better to have the locating sleeves if at all possible.
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Paul  



Joined: 02 Nov 2002
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PostPosted: Sat Sep 10, 2011 1:21 pm    Post subject: Reply with quote

Locating sleeves are a must. Do, or risk a do over.
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MikeJinCO  



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PostPosted: Sat Sep 10, 2011 11:32 pm    Post subject: Reply with quote

Apparently I'm doing the "do over" this time, I'll look around for some of those pins.
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a239947  



Joined: 15 Nov 2015
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Location: Australia

PostPosted: Wed Jan 17, 2018 6:24 pm    Post subject: Reply with quote

I know this is an old thread, but did anybody come up with a fix for the missing locating sleeves.
My block came back from the machinists without them and that was months ago and now i'm trying to put this engine back together and finding that this tiny little sleeve may bring the whole shebang undone.
I know the sleeves are 14x10mm and pelican lists them but i just got an e-mail saying NLA.
Would it be possible to cut down a roll pin to do he job. i noticed these things have pretty thin walls.
I would love to know what other people have done.
My engine is a 924 Turbo so I would like to put something in there as the head is a little soft and will probably move a round a bit.
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Kenodog  



Joined: 25 Jun 2003
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PostPosted: Thu Jan 18, 2018 4:43 am    Post subject: Reply with quote

They are not solid pins. They are more of a thin walled split pin.





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a239947  



Joined: 15 Nov 2015
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Location: Australia

PostPosted: Thu Jan 18, 2018 9:06 pm    Post subject: Reply with quote

yeah the PET calls them tensioning sleeve but they are just a spring loaded dowel sleeve.
I have been seaching the web everywhere and have found some honda dowel pins which are 14mm OD but are 20mm long. i think it could be possible to trim them down with a dremel but they are not split like the originals so there is no tolerance if the fit is not perfect.
I guess it could be worth trying to fit them. If the ID is correct and they fit snug into the block then they could be a good alternative to the originals.
They seem pretty cheap so might give it a try.
i did find a set that seemed perfect, they were 14mmOD X 12mmID and were 11mm long with a split. They were for a scooter engine but I lost the web page and have not been able to find it since.
I just wish things like this were a little more standard in car engines. would make things so much easier.
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MikeJinCO  



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PostPosted: Fri Jan 19, 2018 1:19 am    Post subject: Reply with quote

I made some by using 1/4" pipe and drilling it out then splitting. I did a "How To" a few years ago. With a small drill press it is not very difficult. Make at least half a dozen to make sure you get a couple.
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Ozzie  



Joined: 12 Mar 2005
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Location: Townsville, Qld. Australia

PostPosted: Fri Jan 19, 2018 8:03 am    Post subject: Reply with quote

To locate the head and gasket I cut the head off 4 old head bolts and slotted them to fit a screwdriver.
after fitting the new bolts, just unscrewed them to fit the last 4.
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