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[Joes924]

Well I hate to bring this up.I might have lunched my motor! I had just left Nappa afterwork and was goin home to see my RCI
seats that arrived today and I was driven along and it just started maken a loud noise.
and when I stopped at a stop sign it died wouldnt idle.Got home and but I had kepp my foot in it when the clutch in or it would die.I restarted it in the driveway and it wouldnt idle very good though I was able to get out of the car with the hood already up and put my hand on the throttle.Well it makes a loud knocken sound when you open the throttle,even a little clunken.I wanted to work on my seats so I made the bracket for the passenger side and mounted it I made it out of 1/4 angle & flat stock & bolted it all together.Now Im pretty sure its some kind of knocken or the header cracked apart
or what a rod problem or maybe a valve keeper poped off.I havent investigated at all yet.

Can some of you guys tell me what you think happend.I think I can get a used motor here
next week if need be.Then Ill rebuild my old one this winter right. I thought these motors were stout.They are I guess it just happend.

_________________
JoeD. 1979 924NA
MSD6 rev control/big bore TB/P&P.head
Bursche header/Schneider cam/dialcam


[ This Message was edited by: Joes924 on 2002-08-17 16:44 ]

[PORSCHEV]

Hard to say with out hearing it Joe, But it may have something to do with the valve train rather than the bottom end. A rod bearing can knock, but it won't always makr the engine run badly. I am sure you will find it and let us know. That sucks the big one though!

[Smoothie]

Could it have experienced the proverbial skipped a tooth on the timing belt scenario? That's something you can look at without taking the engine apart. But then, if I know you, wrenches are flyin' and the engine is already apart...

Of course, skipped teeth probably wouldn't account for the noises you're hearing - in an NA at least.

[Joes924]

Well I bought some castrol GTX high mileage
sea type motor oil.Ill change the oil.
and do some other investigating.Sunday

[larso]

Check plugs to see if they're in tact and their condition (maybe one broke off), then figure out if it's knocking only when under load, or at various times (even when not under load. To check to see if it is a valve problem, take the timing belt off, and watch the white mark on the belt go round and round (paint a white spot on it if needed). If you hear the noise while the white mark passes by, it's a cam problem. If you hear two of the noises, in one turn of the white mark, it's a rod prob, ping, piston, etc. (low end). I poured water in my engine to eliminate that it's a rod prob...it's got to be a combustion, exhaust, or leak prob if water helps cure it all! It sounds like maybe an exhaust header popped open or fell off if the engine got rough. But hard to tell.

[Joes924]

Its weird after getting the seats in I changed the oil took off the valve cover and checked plugs everthings good,starts right up
idles runs smooth,no real power loss noticedI had Terri sit in the car and give the pedal and felt around the header underneath couldnt feel no air shooten out,felt around the header connection to the head also. the header is cracked so Ill take that off and have it welded like I was plannen. I think it might be internal I dont know could be that header that was cracked cracked more like you said Lars.Im worken now so it hard to find time should have a day off towards the end of the coming week or mid week when Im done metal framing and waiting for inspections before I hang the drywall thur.and fri. had the plumbers and electritions there. It doesnt smoke
or shake when its idling just makes a hell of a racket I dont know Im thinken the header went to shit somewhere..

[ This Message was edited by: Joes924 on 2002-08-19 14:31 ]

[924RACR]

Yeah, remember an exhaust leak can actually rob power. Try a compression test if you can get your hands on a tester; leakdown would be even better - that'd rule out any fundamental engine damage.

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype