#21  
Old 08-16-2021, 04:30 AM
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Originally Posted by 70pontiaction View Post
And the water is running out thru that exhaust crossover hole, which would put it into the crossover in the intake, but NOT into an intake port.

The heads LOOK like 87cc versions, but can't really tell from the pics.
And there is not a picture of the intake mounting surface.

I agree that if water poured into an exhaust port is actually making it into an intake PORT there is a serious problem.
I didn't realize the 87's had a crossover. Maybe thats what he meant..

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Old 08-16-2021, 07:39 AM
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^^^ that makes 100% sense. water went from exhaust port to EXHAUST crossover.

This week, when I first pulled the rockers off to remove the head, I noticed that two of pivots on the rockers were upside down... the flat part was down on the stud, and the round part was up. I guess I installed them wrong after reinstalling the head. I feel really embarrassed to admit this.

believe HERE was your problem. Now just have to see what damage has been done from said mistake. Posible burt exhaust valves or just depending on how the studs are (tighten to 20 lb torque to seat? or 1/2 turn after zero lash?) designed as to what other components could be affecte. The tighten to seat...could pose alot of damage! valve spring bind, seal damage, pushrod bending.....If they are NOT bottle-necks...then probably just rocker arms, balls, and a little touch up on the valve/seat

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Old 08-16-2021, 09:10 AM
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A lot of helpful information here, thank you. I'm sorry I didn't have time to reply yesterday, had to work and didn't get a chance to try anyone's suggestions.

To answer some of the questions, all the cylinders had between 160 and 165 psi of compression when I tested, except 2 and 4, which had 0. Those are dry test numbers, I didn't try wet.

I did reuse the head gasket, The engine had never been run at that point. I didn't respray the block, I assume the copper you see there is from the original application. I didn't respray the head either.

I can't remember what we did with head bolts, I don't see them itemized on the invoice.

Yes, they are 87 cc heads. It's possible the water was running out the cross over, the intake side was down when I filled the port.

When I get off work tonight, I will try some of the suggestions above and answer the other questions. I ordered a valve compressor and a leak down tester. Sounds like the best of course of action when those come in would be to reinstall the head and do a leak down test.

Really appreciate all the input.

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Old 08-16-2021, 04:15 PM
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No need to reinstall the heads. Zero compression = a huge leak, it should be pretty obvious what's going on by physical inspection.

Set the head up so the deck surface is on top and level, then fill the chambers. If there is a big enough valve leak to cause zero compression, the water will pour out of whichever port has the problematic valve.

Alternative idea - pull the valves out of the heads in those two cylinders and visually inspect the seats and valves. If nothing is obvious, get some machinist bluing, spray the seat area then whack the valve against the seat by hand. The impression left in the bluing will show if the valve is not making good contact with the seat - the impression should be uniform all the way around and leave a uniform blue band on the valve also - and the mark on the valve should be on the seating surface and leave a small margin around the outside edge of the valve.

Doing this will also reveal if you have tight guides or bent valves.

Check your pushrods. Are they all straight? Any damage to the ends where they sit in the lifter or the cup in the rocker arm? Check the cam, how do the lobes and lifters look?

If all that checks out, then the problem has to be with the pistons & rings. Bring a piston up to TDC and see if it walks/wobbles in the bore. How do the finishes on the cylinder walls look?

I've worked on engines with blown head gaskets, burned valves, and cracked rings/ring lands and they always showed at least some compression on the problem cylinder and the problems were visually obvious. Zero compression means a BIG problem that has got to be visible.

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Old 09-11-2021, 11:05 PM
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Finally had some time to try the troubleshooting methods suggested.

Here's what I tried:

1. Filled the chambers with water. No water leaked out of the valves.
2. Tried Cliff's suggestion to pressurize the intake/exhaust ports with air while water was in the chambers. I was able to get some minor bubbles out of the two exhaust valves on the dead cylinders, but as many said, didn't seem to be enough to make the cylinder have no compression.
3. Pulled the valves. Not an expert, but the valves and seats looked the same on the two dead cylinders as the the ones with good compression.
4. checked the pushrods, they look straight to me.
5. checked the cylinder walls. They look good, crosshatching still visible on all cylinders. Very minor scuffing on one of the dead cylinders... perhaps due to fuel washdown?
6. Finally, took Blue bird 68's advice to reinstall the head with the old head gasket and fill the cylinders with compressed air to see where the leak was. What I found was with the valves adjusted, I was getting air past the valves when they should have been closed.

I spend a lot of time watching youtube videos and adjusting the valves. Many guides online suggest tightening the rockers just so the pushrods have no up/down play/can't be turned by hand. Then tighten 1/2 to 3/4 turn to set preload. What I found was that almost any preload, even 1/8 turn, was enough to make the valves leak and drop compression to almost nothing. I was able to replicate this on any cylinder, not just the two that had originally had no compression. By tightening the nut on top of the rocker just so the pushrods stopped turning, and then locking them down, I was able to get healthy compression in all cylinders.

I don't understand why this is. Is there something wrong with my valve adjusting technique?

I do regret not doing a more through diagnosis before pulling the head... it seems like a simple valve adjustment with compression test to verify the valves were sealing would have clued me in on the problem.

  #26  
Old 09-12-2021, 09:06 AM
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Maybe with the engine sitting for many years, the oil in the lifters has turned to gunk/thickened and won't let the internals of the lifters work properly.

  #27  
Old 09-12-2021, 09:16 AM
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The lifters weren't full when adjusting or you didn't stop twirling pushrod when it 1st contacted the lifter. (took up all the slack)

I used to adjust them while engine running. This keeps the lifter pumped up.

Initial install I just take up the slack between the pushrod/rocker and the lifter with lifter on base circle of cam. (then start and adjust)

But I haven't ran hydraulics in years.


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  #28  
Old 09-12-2021, 09:52 AM
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I'm with John on adjustment procedure didn't go right.

I've had lifters that took a minute or two for plungers to leak down. But they did and everything was fine.

With intake and valley pan off you could watch this happen.

Being a 2013 build is going back to when noisy lifters was a big deal and lots of builders were using solid roller lifters to avoid the noise problem.

Need to look
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  #29  
Old 09-12-2021, 10:27 AM
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Adjusting valves has nothing to do with the other half of his issue, that being a coolant leak!

The head gasket failed for whatever reason and all you can do now is.

1) confirm that the block deck and head deck is straight within,002”.

2) confirm that the head bolts are not bottoming out.

3) confirm a correct torque is being used and that the torque wrench reads within 5 lbs of dead on above 80 lbs.

4) pressure test the head or bolt it on and the pressurize the cooling system before wasting time installing the valve train to start the motor,
The heads deck surface needs to be like a mirror finish if you want good gasket life!

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Old 09-12-2021, 10:56 AM
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johnta/Quick-silver: I wondered if the lifters might be solid based on the way they were acting. I pulled one. Looks hydraulic to me (I can see the plunger/keeper inside). See pictures. I see what you are saying about the lifters pumping up. I have adjusted valves years ago on a running stock engine by sound as well. I guess I could do that here. Why do all demonstrations show adjusting the valves on an engine that's not even in the car? Those lifters haven't had a chance to pump up.

steve25: There never was a coolant leak. I think I made a false assumption on the head gasket being bad based on the two cylinders that had no compression being adjacent. If I had done a more through diagnosis, I wouldn't pulled the head in the first place.
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  #31  
Old 09-12-2021, 01:36 PM
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Can you push down on the pushrod cup and get movement? If the cup is frozen in place then cranking in the preload from zero lash will hang the valve open. Since you only had problems on only a couple lifters, I'd rule out the possibility of solids.

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  #32  
Old 09-12-2021, 02:26 PM
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Quote:
Originally Posted by Jonsey View Post
Why do all demonstrations show adjusting the valves on an engine that's not even in the car? Those lifters haven't had a chance to pump up.
Pre-load on a dry lifter happens pretty much instantly. You watch, measure and set it where you want. With "good" lifters it's not a problem and how they were built at the factory.

A lifter full of cold oil can take a while to leak down. Cold 40wt oil makes them leak real slow. Weak valve springs makes them leak real slow.

Don't know what lifter body lunatti uses to make their solids, So can't help with that.

Clay

  #33  
Old 09-14-2021, 03:53 PM
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Did you ever check the pushrods for straight? Rolling them on a flat piece of glass will expose any that are bent. Looks like #4 exhaust is maybe hanging open letting exhaust in, blackening that valve. That would explain the popping if that exhaust was open when #6 was firing. If the nick in #2 is leaking, that would explain both. With rockers installed wrong, it might have limited their travel. You might want to check them for marks on the flat side where they might have hive around the valves. If #2 intake wasn't opening, I wouldn't expect much compression, and if it was hanging open, you would have no compressed fuel to burn.

  #34  
Old 09-14-2021, 04:01 PM
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Yes, the pushrods were straight, as far as I could tell. Rockers have small marks in the anodized coating where they were installed incorrectly but don't seem damaged.

I was able to get compression on those cylinders with less preload (basically none) so I'm guessing the first time it was popping was the incorrectly installed rockers. When I noticed they were installed wrong, I reinstalled them correctly but adjusted with too much preload, so the valves were still open. Would have been obvious if I had pressurized the cylinder. A valuable lesson in spending the time to really know what the problem is, not jumping to conclusions.

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Old 09-14-2021, 04:03 PM
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Good news!👍

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  #36  
Old 09-16-2021, 05:27 PM
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I don't get it. #2 and #4 look like they were just installed and have never seen spark. If you had fuel and spark, compression or not, the bad cylinders would fire and would be sooty and wet fouled, not squeeky clean. You never had fire in either of those holes.

Was your oil also full of gasoline? With no fire, fuel would leak past the rings into the crankcase in addition to blowing out the exhaust in a mist and drip from the tailpipes..

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Old 09-16-2021, 06:11 PM
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Quote:
Originally Posted by Jonsey View Post
johnta/Quick-silver: I wondered if the lifters might be solid based on the way they were acting. I pulled one. Looks hydraulic to me (I can see the plunger/keeper inside). See pictures. I see what you are saying about the lifters pumping up. I have adjusted valves years ago on a running stock engine by sound as well. I guess I could do that here. Why do all demonstrations show adjusting the valves on an engine that's not even in the car? Those lifters haven't had a chance to pump up.

steve25: There never was a coolant leak. I think I made a false assumption on the head gasket being bad based on the two cylinders that had no compression being adjacent. If I had done a more through diagnosis, I wouldn't pulled the head in the first place.
I have these exact lifters in my engine. On a 7/16-20 stud, they require right at 3/4 turn past zero lash per their instruction sheet.

Mine are noisy and in my quest to solve the noise, I've spoke with techs at lunati who mentioned that the lifters are cleaned/packaged with a water based solvent that doesn't pair well with oil and can cause sludge in the plunger. Their instruction sheets specifically state not to clean the lifters however and not to soak them in oil before installation, just dip them for lubrication and install.

My anecdotal guess here is that the engine was built, those lifters installed, and since you let the engine set for a couple years during restoration, a couple of the lifters developed sludge enough to make them act like a solid lifter. Your preload was hanging the valve open as a result.

Considering you can get compression on those cylinders by not applying pre-load, that's where I would start. Take the lifters from the two offending cylinders and see if you can depress the plungers by hand. There's 120 thousands of travel in those lifters so you can absolutely tell if you depress the plunger.

If they are solid or barely move at all, you know what you're up against. I would in that case, get some mineral spirits and disassemble and clean each lifter (all 16). Re-install and adjust the valves to zero lash +3/4 turn (I go another 1/8th on the set skrew after) and run your compression test again.

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  #38  
Old 09-16-2021, 06:25 PM
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Back in the day, zero lash was worth another 500 rpm up top.

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  #39  
Old 09-16-2021, 08:03 PM
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Quote:
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Back in the day, zero lash was worth another 500 rpm up top.
If you had good lifters. Not so much these days.

  #40  
Old 09-16-2021, 11:19 PM
Jonsey Jonsey is offline
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Neighborscomplaint, the oil doesn't smell like fuel.

JLMounce, I used to a pushrod to test the plunger on each lifter on the passenger side. The amount I could depress each lifter varied widely from quite a bit to not at all. I'll see about disassembling them for cleaning.

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