Author Topic: tell me wht tey f***d up :|  (Read 1935 times)

Offline willard

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tell me wht tey f***d up :|
« on: October 23, 2010 - 11:44:31 AM »
Yesterday I finally got my car back. The engine was reassembled with new pistons, rings, gaskets/seal. When accelerating under load it made a dense cloud of brownish smoke. I drove it lika a baby - never over 3.5 kRPM...
Today I hooked up a vac gage and stumbled...
before rebuild it was a steady 15" hg (low comp pistons), now look at this:


bent valves? spring? what ya think? At idle it tickles between 9 and 15 in HG, at 1000 rpm it is steady 18", opening the throttle more it raises to 20" and then drops.

Moreover there is some noise (ticking) from the right bank but i cant pinpoint it. Ticking seems to be related to rpm. It seems they are gonna rebuild it once again.

1970 383 R/T SE




Offline 72cudamaan

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Re: tell me wht tey f***d up :|
« Reply #1 on: October 23, 2010 - 11:50:26 AM »
Looks like weak springs (and,or) valves not sealing properly.  :dunno:
If I cant fix it, it's broke
 
Andy  (phukker whither)

Offline willard

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Re: tell me what they f***d up :|
« Reply #2 on: October 23, 2010 - 12:14:02 PM »
I guess it sth with valves or guides.
The springs, heads, cam are were not replaced, however they did checked the heads, milled them just a bit and mated the valves with seats (don't know the proper english term for this procedure).
If I didn't dump lot of $$ in the engine rebuild I'd pull the valve covers in a minute but I still have the workshop's warranty...
1970 383 R/T SE

Offline ksierens

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Re: tell me what they f***d up :|
« Reply #3 on: October 23, 2010 - 12:30:24 PM »
mated the valves with seats (don't know the proper english term for this procedure).

It's called lapping  :thumbsup:
1970 Triple Black Challenger R/T  440 Six Pack - 4 Speed - 3.55 Dana
Kurt - SE Michigan

Offline willard

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Re: tell me what they f***d up :|
« Reply #4 on: October 23, 2010 - 03:30:35 PM »
Thanks.
Most of online guides associates such vacuum gauge behavior with worn guides. I'm curious how is this possible if the valves and headsare the same as before. Maybe they mismatched valves that were mated with certain guides and now thy leak. This may also be the source of that cloud of smoke on acceleration.
1970 383 R/T SE

Offline 72cudamaan

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Re: tell me what they f***d up :|
« Reply #5 on: October 23, 2010 - 08:26:01 PM »
I guess it sth with valves or guides.
The springs, heads, cam are were not replaced, however they did checked the heads, milled them just a bit and mated the valves with seats (don't know the proper english term for this procedure).
If I didn't dump lot of $$ in the engine rebuild I'd pull the valve covers in a minute but I still have the workshop's warranty...

How is it that they " rebuilt" the engine and didn't rebuild the heads. If that's the case, the whole job may be suspect to me. IMHO  :dunno:
If I cant fix it, it's broke
 
Andy  (phukker whither)

Offline Moparal

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Re: tell me wht tey f***d up :|
« Reply #6 on: October 23, 2010 - 08:52:23 PM »
well, all i saw was the gauge in the vid. But a couple of questions for you.

Is it possible you have an exhaust manifold leak for the ticking like a gasket?

and if the intake gasket valley pan isn't sealed right, it will suck oil and air and smoke and give a bad reading if you have any vacuum leaks. so are you sure you don't have a vacuum leak at the carb base plate?  Are you sure the intake gasket isnt leaking?  Are you sure the cam was degreed in and set to the right center line? The engine could be ok, but have these particular problems. and if you installed the intake, carb and exhaust, it would reflect back to you. If it was the timing of the cam vs crank position, then it would be them if they supplied the chain set up. Some timing chain sets are not even close dot to dot depending on quality.

Offline willard

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Re: tell me wht tey f***d up :|
« Reply #7 on: October 24, 2010 - 04:01:51 AM »
Year ago the engine had no leaks, run properly but had NP366 pistons and very low compression. During the car rebuld the shop disassembled the engine and swapped the pistons for KB400, they also slightly milled the heads and they measure 85 cc, the block deck was also milled a little due to corossion by one of water channels.

They reassembled the motor with my old lunati 60302 cam, valves, new valve seals and all new gaskets, rings plus steel 0.020 head gaskets. Then they tune it with O2 sensor. When I took the car from the shop it was idling ok, better than year ago. It was uring the trip home (110 miles) when my bro spotted that cloud of black smoke after heavier acceleration.

During the car resto I spoked to the engine man in the shop several times: they checked the bearings, laped the valves but didnt tell a word that valve guides are shot.  I asked about degreeing the cam but in this country NONE does it. They dont even have a degree wheel (bear in mid this is the best workshop here and they maintain their own mopars too). They just lined the dots, like I did when installing the cam the first time. It was running fine.

Under the hood there is no ticking noise of leaking manifold gasket, the valley pan and carb base look ok but I'm gonna spray the joints with carb cleaner and look for air leaks.

I guess it's the valve guides and that would also cause smoking during acceleraton - when pistons suck oil thru/by the guides (?).
1970 383 R/T SE

Offline dutch

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Re: tell me wht tey f***d up :|
« Reply #8 on: October 24, 2010 - 04:27:09 AM »
wouldn`t the smoke be blue if it`s burning oil?  Black smoke would guide me in carb adjustment direction...  :dunno:
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