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Topic Review (Newest First)
05-23-2013 05:15 PM
UPandComing glad it all worked out for you.
03-07-2013 04:43 PM
Northern Chevy Oh I get you now, I just associate sludge with the topside of heads, lifter valley and oil pan. So where it came from, ether the PCV valve and may or may not mean excessive ring blow by or you also had intake gaskets leaking from underneath, this is assuming your valve guide seals really are good .. hope so after having the heads checked out!. I would think you would have been going through a certain amount of oil, consumption wise then in the last while.
03-07-2013 03:43 PM
71fj40guy
Quote:
Originally Posted by Northern Chevy View Post
I wonder if the sludge was that bad that it held the oil back from flowing out of the heads { assuming you meant sludge on top of the heads } that it helped promote the PCV to suck up oil .. its only a thought. Do you know the past history in how often the engine oil was changed and what brand of oil was used and what I am driving at there is the fact the oil wasn't doing a very good job at keeping the sludge at bay or somewhere along the line the PCV valve plugged up, a thermostat not keeping the engine up to temperature etc. I realize the humidity factor of your area could be an issue in keeping an engine cleared out of moisture but can't be worse then the south eastern states or for that matter up here in the winter.

I just know with my own 1995 350ci, in sorting out my own engine miss issues I had the valve covers off and I was surprised to see how clean it was, just a slight discoloration film on the rocker arms and the head surfaces were spotless and only a thin layer of build up in the very front end of each valve cover. I have used 0W-30 synthetic all along from Imperial .. now Mobil and change it every 3000 miles and the engine has 186000 miles on it. Hard to say if it would have looked the same with another oil as I have nothing to compare with.

It may not hurt assuming the combustion chamber cleaning products work, to run some through on a regular basis and hopefully keep the carbon build up down. At least as time goes on you can pop the valve covers off and see how the top side of the heads look.
The sludge and oil was actually on the cumbustion chamber side along with the inside of the head. I have no doubt that it was effecting the way the valves worked. There was a lot of oil getting sucked into the intake.
03-07-2013 12:18 PM
Northern Chevy I wonder if the sludge was that bad that it held the oil back from flowing out of the heads { assuming you meant sludge on top of the heads } that it helped promote the PCV to suck up oil .. its only a thought. Do you know the past history in how often the engine oil was changed and what brand of oil was used and what I am driving at there is the fact the oil wasn't doing a very good job at keeping the sludge at bay or somewhere along the line the PCV valve plugged up, a thermostat not keeping the engine up to temperature etc. I realize the humidity factor of your area could be an issue in keeping an engine cleared out of moisture but can't be worse then the south eastern states or for that matter up here in the winter.

I just know with my own 1995 350ci, in sorting out my own engine miss issues I had the valve covers off and I was surprised to see how clean it was, just a slight discoloration film on the rocker arms and the head surfaces were spotless and only a thin layer of build up in the very front end of each valve cover. I have used 0W-30 synthetic all along from Imperial .. now Mobil and change it every 3000 miles and the engine has 186000 miles on it. Hard to say if it would have looked the same with another oil as I have nothing to compare with.

It may not hurt assuming the combustion chamber cleaning products work, to run some through on a regular basis and hopefully keep the carbon build up down. At least as time goes on you can pop the valve covers off and see how the top side of the heads look.
03-06-2013 10:10 PM
71fj40guy
Quote:
Originally Posted by Northern Chevy View Post
So throughout the repairs or tear down of the top end, did you ever really nail down what was causing this "rattling" ... was it valves floating with really weak springs or perhaps preignition due to an extreme amount of carbon build up and was that from too rich a fuel mixture or was it using excessive amounts of oil ? . Then the matter of the mystery air loss in two cylinders as you pressured them up. Just curious to find out what was really going on inside that engine.
I'm going with the extreme amount of carbon. It was really caked on the piston faces and the heads were covered in sludge. This was most likely caused by oil getting sucked up through the PCV valve since my valve covers had no baffles. It also looked like there was an issue on the old head gasket between those 2 cylinders. The gasket came of clean and you could actually see an issue.
03-06-2013 08:38 PM
Northern Chevy So throughout the repairs or tear down of the top end, did you ever really nail down what was causing this "rattling" ... was it valves floating with really weak springs or perhaps preignition due to an extreme amount of carbon build up and was that from too rich a fuel mixture or was it using excessive amounts of oil ? . Then the matter of the mystery air loss in two cylinders as you pressured them up. Just curious to find out what was really going on inside that engine.
03-06-2013 08:05 PM
71fj40guy Finaished up the valve adjustment and took it for a test drive.....So that's how it's supposed to run.....What a difference. I want to thank everyone for all their advice. You were all a great help.
03-05-2013 08:09 PM
71fj40guy Quick update, finally got the FJ40 running and idling smooth. Timing is all set and I finished half of the final running valve adjustment. All I have left to do is finish the the passenger side valves.
So far all of the previous issues are gone. No detonation/valve chatter, no single tick when I turn off the motor, all the pistons are firing perfectly. Can't wait to test drive it tomorrow night.

On another note....I really like the MSD Digital E-Curve distributor. After I learned how to set it up it's so easy to deal with. Nothing like being able to change the curve in just a few seconds.
03-04-2013 10:38 PM
spinn Yes , degree and measure.

Okay , no multi key. I was trying to mind read.
03-04-2013 10:32 PM
F-BIRD'88
Quote:
Originally Posted by spinn View Post
I think the cam can be advanced 6 by using the dot to A on the timing chain gear set. He could have checked that visually at tdc.
This is supposed to be a GM 350-290hp crate motor. It should not have a multi key crank gear on it.
Never assume the multi key crank gears actually will move the cam accurately,
by the desired amount. (they don't)
You want to move the cam accurately by first determining its real installed position first. By degreeing it.
03-04-2013 10:17 PM
spinn I think the cam can be advanced 6 by using the dot to A on the timing chain gear set. He could have checked that visually at tdc.
03-04-2013 10:01 PM
F-BIRD'88 What was at 6deg advance? Did you degree in the cam with a degree wheel and dial indicator on the lifter or....?
6deg advance based on what/ ? the .050" lifter rise open close events? or...?

What is/was the .050" (@ the lifter) intake closing point ABDC?

Do not go by the point of max lift of the cam lobes or the point of split overlap as this cam is a non symetrical cam. The intake and exhaust sides of the lobes are different and the in and ex lobe is not the same lobe.
You cannot determine the advance/retard phasing of a non symetrical cam by laying a ruler across the lifters @ TDC
or comparing the points of max lobe lift.

You need to degree the cam to determine its installed position based on the .050" (lifter rise) open close event timings.

You are primarily concerned with the measured .050" (lifter rise) intake closing point ABDC.
It should check @ 47deg ABDC @.050" and you want to move that to 38deg ABDC.
03-04-2013 09:46 PM
71fj40guy
Quote:
Originally Posted by F-BIRD'88 View Post
Too bad you did not take advantage of the situation and degree and advance the .450"in.460" ex camshaft in this motor.
( If you were to degree it you would find it is retarded (115in/113ex C/L's) 114LSA (retarded by 1deg)
Moving the cam to a new 107in/121ex C/L position (7degree advanced) will wake it up and make more torque in this low cr engine. as the intake valve will close sooner.
This cam was GM's origional 1969 11:1 ccompression 350-350HP L-46 cam.
As installed it is a mis match @8.5:1cr. It need to be advanced.

If the new head gasket is thicker than the old stock head gasket the compression ratio wil now be even lower.
Should have wacked some off the heads (.050") and used a felpro shim head gasket.
I would have home ported the heads too.
When I had the heads off I put it to TDC and it was already set to 6 degrees advance.
Unfortunately I ran into more delays today. Got everything put together, but when I fired her up she ran for about 20 second then died. Need to trouble shoot tomorrow and do the final dial in on the timing and valves.
03-04-2013 07:23 PM
F-BIRD'88 Too bad you did not take advantage of the situation and degree and advance the .450"in.460" ex camshaft in this motor.
( If you were to degree it you would find it is retarded (115in/113ex C/L's) 114LSA (retarded by 1deg)
Moving the cam to a new 107in/121ex C/L position (7degree advanced) will wake it up and make more torque in this low cr engine. as the intake valve will close sooner.
This cam was GM's origional 1969 11:1 ccompression 350-350HP L-46 cam.
As installed it is a mis match @8.5:1cr. It need to be advanced.

If the new head gasket is thicker than the old stock head gasket the compression ratio wil now be even lower.
Should have wacked some off the heads (.050") and used a felpro shim head gasket.
I would have home ported the heads too.
03-04-2013 01:16 PM
71fj40guy Quick update whitle I wait for the RTV to setup. I hooked up my airline adapter to the 4 and 6 cylinders and the air leak is gone. So it looks like it was either the built up crud in the head or the old head gasket that was the air leak issue.
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