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Mike
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I was waiting to hear what your initial timing was (after confirming the alignment of the TDC timing marks).
Did you ever get a chance to do this?

One other thing cam to mind and I can not recall if this topic ever came up within this discussion.
Did you ever change the oil... or check the oil for a "gasoline smell" after the higher fuel pressure issue?
I'm starting to wonder if enough raw fuel leaked from the carb to contaminate the oil.
 

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Won’t matter now. He seems intent on tearing into the motor. Trust me, after looking at the pictures there is plenty of antifreeze in the oil.
 

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Discussion Starter #223
I was waiting to hear what your initial timing was (after confirming the alignment of the TDC timing marks).
Did you ever get a chance to do this?

One other thing cam to mind and I can not recall if this topic ever came up within this discussion.
Did you ever change the oil... or check the oil for a "gasoline smell" after the higher fuel pressure issue?
I'm starting to wonder if enough raw fuel leaked from the carb to contaminate the oil.
I never was able to verify anything to do with the timing, as the engine would not start at all.

I did check the oil after the fuel pressure got high and it had a slight smell of gasoline so I did change the oil and filter.

Now, here may be where the problems started, but I am not sure. When I changed the oil, I put 10W30 full synthetic in it. Now I have read since then that the new oil is not the same as the older oil was and is very bad for these engines. That could have caused my problems if it wiped out the cam. It seems like the problems started around that time.

I pulled the intake to check the condition of the cam and there is definitely some wear, as evidenced by the shiny spots. I am not sure if the lobes are completely wiped, or not. Also, I wanted to verify what lifters are in it. There is definitely some play in all the pushrods when the valves are closed, which should not be the case with hydraulic lifters. As a minimum, the valves were in definite need of adjustment but I'm afraid there are still issues that are going to require the heads to come off.

I got a cylinder leak down tester and checked the number 2 cylinder and it was definitely blowing a strong stream of air from around the exhaust valve. I had the cylinder at TDC and there was no pressure on the pushrods, so both valves were closed.

Just for the hell of it, I decided to test the other cylinders and ALL of them are blowing air. Numbers 4 and 6 were blowing strongly out of the intake ports. Number 8 was blowing from somewhere but I couldn't tell exactly where.

I also checked cylinder 1 and it had the same issue. I believe it was blowing out the intake ports on the head.

My only question is, is it ok to do the leak down test with the intake off? I don't see a problem with it, since all the rockers were completely off of the valves, so they should have been completely closed. The only leakage should have been through the gaps in the rings, which should have been the normal 5-10%.

I have no idea what would cause all of the cylinders to be leaking as bad as they were. The compressor was set at 100 psi and it could not pump fast enough to build up enough pressure to shut off.

I'm lost at this point and am just hoping that the bottom end is ok and the issue can be resolved with figuring out the valvetrain. Unless I am doing something wrong and you can point me in the right direction.
 

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Discussion Starter #224
Won’t matter now. He seems intent on tearing into the motor. Trust me, after looking at the pictures there is plenty of antifreeze in the oil.
Believe me, tearing into the motor was the last thing I wanted to do.

The antifreeze in the lifter valley is from removing the intake. I did soak it up, even making sure to get around the pushrods on the top of the lifters. After soaking it up, I poured fresh oil over everything and covered it with a plastic bag.

I certainly don't have an unlimited budget and I hoped to be on the streets by now, but I want to have a drivetrain that is as bulletproof as possible and it never felt right to me not knowing anything about the internals of the engine. The guy I got it from claimed to have gotten it as a trade and didn't know anything about it except that the transmission had been built by a shop in Gainesville and it had a 3500 rpm stall converter.
 

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The guy I got it from claimed to have gotten it as a trade and didn't know anything about it except that the transmission had been built by a shop in Gainesville and it had a 3500 rpm stall converter.
Tim, I know you have a lot on your plate on the engine side...but if you are pulling the motor to deal with what that,,,,,, might consider going with a lower stall (if 3500 is what you really have) if this is primarily a street car. 2200-2400 unless the cam is radical
 

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Blowing air through the intake ports with the valves closed is not a good thing. Sounds like a new set of heads. Might be cheaper to nab a set of new aluminum heads rather than rebuild the existing ones. Rings? With heads that bad you never know. Do you put new heads on and check it again or re-ring it now. Bearings? Maybe get your your oil analyzed for bearing material? Sounds like a complete tear down either way.
 

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you can take an oil sample and send it off for analysis. If you have wiped out cam lobes with the new oil (due to not enough Zinc and other additives) the test will show it right away. And if it comes back clean you can probably focus on the heads and get them reworked. Of course you may be able to tell that just looking at the drain pan too if you see lots of metal particles.

For future reference, I use Rotella 10/40 in my flat tappet cam engine because it has the needed additives.
 

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Discussion Starter #228
Blowing air through the intake ports with the valves closed is not a good thing. Sounds like a new set of heads. Might be cheaper to nab a set of new aluminum heads rather than rebuild the existing ones. Rings? With heads that bad you never know. Do you put new heads on and check it again or re-ring it now. Bearings? Maybe get your your oil analyzed for bearing material? Sounds like a complete tear down either way.
I agree that the air leakage is really bad. Going to pull the heads this afternoon or tomorrow and see what is going on.

I am thinking the same as you as far as rings and bearings go. If the cam wore down that quickly, then there almost certainly has to be some impact on the other surfaces that require lubrication.

I would be devastated if I put money into the heads and sealed everything up on the top end only to find that the bottom end is in need of attention, too. Having to tear it back down would certainly not be a good thing.

Rings and bearings are relatively cheap if the rest of the rotating assembly is ok.
 

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Discussion Starter #229
you can take an oil sample and send it off for analysis. If you have wiped out cam lobes with the new oil (due to not enough Zinc and other additives) the test will show it right away. And if it comes back clean you can probably focus on the heads and get them reworked. Of course you may be able to tell that just looking at the drain pan too if you see lots of metal particles.

For future reference, I use Rotella 10/40 in my flat tappet cam engine because it has the needed additives.
Thanks for the reference on the oil. I have read that a lot of people run the diesel oil because it still has the zinc and other stuff in it. I was considering going with a roller cam if this was going to be a constant issue but can go flat tappet if they do well with the right oil.

Where would I send the oil sample to?
 

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Discussion Starter #230
Tim, I know you have a lot on your plate on the engine side...but if you are pulling the motor to deal with what that,,,,,, might consider going with a lower stall (if 3500 is what you really have) if this is primarily a street car. 2200-2400 unless the cam is radical
Thanks. I know 3500 is on the high side for street use but it does/did have a healthy cam in it. I really liked the sound when I first got it. If I can find out the specs on it, I plan to go back with something similar.
 

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Im by no means as experienced as these other guys however, at this point, you're better starting with a clean slate with known parts etc. Set a budget and do the best you can with what you have left.
 

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Discussion Starter #232
Im by no means as experienced as these other guys however, at this point, you're better starting with a clean slate with known parts etc. Set a budget and do the best you can with what you have left.
I agree. I am willing to spend the money to build it right with good parts so I know what I have and what was done to it.

Like I said in a previous response, I don't have an unlimited budget, but I want it to be right when I get it done.
 

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If the compression check in post number 1 is correct there is no way you have that much air leaking past the valves with the possible exception of cyl #2. You apparently are not at each cylinders’ top dead center. Rerun the compression check and post the results.
 

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Thanks for the reference on the oil. I have read that a lot of people run the diesel oil because it still has the zinc and other stuff in it. I was considering going with a roller cam if this was going to be a constant issue but can go flat tappet if they do well with the right oil.

Where would I send the oil sample to?
I've used Blackstone labs before, they seemed reasonable and quick turn around with pretty good commentary on the results. Blackstone Laboratories
 

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Discussion Starter #235
If the compression check in post number 1 is correct there is no way you have that much air leaking past the valves with the possible exception of cyl #2. You apparently are not at each cylinders’ top dead center. Rerun the compression check and post the results.
The only cylinders I got to TDC were 1 and 2.

#2 was blowing out around the exhaust valve.

#1 was out the intake ports on the head (intake is off).

On the others, I just took the rockers off of the valves and blew air into the cylinders with the leak down tester. I expected the gauge to drop down because the cylinder was down in the bore some but figured it would stabilize and hold pressure to some degree. Shouldn't it basically be a sealed cylinder, if the valves are both closed, with the exception of the small amount that leaks down through the gap in the rings?

There was definitely a strong push of air out of the intake ports on 1, 4 and 6 and 8 was blowing air from somewhere but I couldn't pinpoint where.

I was going to do another compression test before I did the leak down test but didn't want to pump antifreeze out of the water jackets into the crankcase via the lifter valley. Plus, there would be no oil circulation due to the intake and distributor being off.
 

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What gauge are you using. Yes, with the rockers off it should hold pressure. I just don’t know how you went from 180-190 lbs compression to so much air leaking past the valves.

Also, a shiny cam is not a ”wiped“ cam. When a cam goes bad it is usually enough to easily feel with your fingernai.
 

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Also, a shiny cam is not a ”wiped“ cam. When a cam goes bad it is usually enough to easily feel with your fingernai.
And you often won't be able to pull the lifter out of the bore.
 

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Discussion Starter #238
And you often won't be able to pull the lifter out of the bore.
Some of the lifters do seem to be pushed farther into the lifter bores than they should be. I have not tried to pull any out, though.
 

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Discussion Starter #239
What gauge are you using. Yes, with the rockers off it should hold pressure. I just don’t know how you went from 180-190 lbs compression to so much air leaking past the valves.

Also, a shiny cam is not a ”wiped“ cam. When a cam goes bad it is usually enough to easily feel with your fingernai.
Neither do I. That's what I don't get about this whole thing. It truly has me baffled.

I am using the Maddox leak down tester from Harbor Freight but I could do the same thing by just hooking up a compressor directly to the plug hole. It is just blowing through. So much so that the compressor kicks on and doesn't shut off because it doesn't build up enough pressure.

I will try to get some video of it when I get home. If I hold some tissue up to the intake ports, I am sure you will be able to see it blowing from the air coming out.
 

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And the rocker arms are completely removed?


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