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Im at work but I can catch a quick break for this. So you need the cyl your testing at tdc of the first aka compression stroke. I dont remeber standard psi off hand so youll have to look it up. I think its 120 or 60 but i work with psi for a living and sometimes it gets mixed up. With proper pressure or at least close and the cyl you are testing at the tdc of cmpression stroke you will need to listen for air leakage. A mech stethascope helps. Pull the valve covers and listen where you suspect leakage. Also look for bubbles. Your leakage numbers are climbing as you put more air into the system because your valve s are open. The leak detector system is designed to help you find a valve that is not working, worn rings or other head problems and measure how badly said component is not doing its job. Let me know.
When I did this process last night on #2 cyl at first I adjusted pressure to about 30 and slowly rotated the motor (clockwise/tords the radiator) until I felt resistance. I then started to crank it up even more as you see. Yes I am holding the bar and ever so slightly moving the bar tords me (an inch of movement) as the pressure was fighting me and trying to kick the bar back tords the firewall. As the pressure went up no leaks heard. You would think the higher you go the worse the "leak" would be heard. But as I do this the gauge indicates 0 leak as seen above.
How to use cylinder leak down tester...
1. Set whatever cylinder to TDC.
2. Without leak tester attached to cylinder, set it to 0% leakage.
3. Attach leak tester to cylinder.
4. Record results.
^ im with stupid, you must set baseline at 0% leakage
Im not sure why its doing that. Whenever I use the tester I end up putting as much air in as I can with it at tdc of the cyl Im testing. With my 454 I didn't have to hold the crank because when the piston was perfectly tdc on compression stroke the piston would stay in place. I know its right when I dont hear any huge billowing amount of air pouring out of an open exhaust valve down the tail pipe. Your looking for a very small oil leak vs a stuck valve or something like that which is what the tester was designed for. The oil is getting in the cylinder so the air pressure that you put in can also get out. You have to look and listen for the leak then. If you are trying to rule out the rings, you have already done that ops check. Although your numbers from earlier with your compression test were a little varied, then didn't seem grossly over or under and the compression test with dry then wet cylinders is a really good test. Keep at it man, um or woman, Ill keep helping anyway I can.
Sort of an update. I really don't have time for this car anymore so I'm most likely putting it for sale but....
I did a leakdown test by setting it to 0 then plugging it in (which is 100 psi instant into the cylinder). Well it needed convincing to get the piston perfect so it would not leak out the valves. Testing cyl 2.
As I did this and with the crank not trying to spin I was reading 15% leakage. If I rotated the crank a bit (force on the bar so it would not rotate back) It came down to about 3-5% which is fine for me. I even did this for cyl 5 which read basically the same thing. So there are 2 ways to do this test which I do not like. The set and plug in way. Or rotate until resistance, crank pressure and hold bar.
Even with my buddies csrt4 I did it by rotating the crank until there was resistance/cranked the pressure up and held the bar. He had 20% on all 4. Ripped the head off and hairline cracks on every cylinder.
Plus this is a regal and an auto. I see stick cars being tested on youtube and set the ebrake and put in gear so it has no way to rotate at all unlike an auto could unless you hold the crank.
I think I can rule out rings hopefully. But how in the hell is the spark plug wet up the threads?????? Everything is bone dry on the head and was on assembly. I was looking on my original motor and thinking how in the hell is this possible? I can clearly see the exhaust valve but the intake I cannot. If something on the intake side is doing this I cannot see until ****s apart. Possible it could be. Bad intake gasket seal is really the only other cause if the rings are mint unless there is something wrong with the valve guide seal. Or a cracked head but its iron so that's not very possible.
These heads can crack can't they? Or is that just the valve guides that crack?
What causes this?
Does anyone have pictures of this?
That's what I thought. I know I've seen a picture of a magnafluxed set of heads that showed the cracks between the valves. Iirc it's because the area is so thin there.
I'd like to see pictures. Considering cyl #2 is pretty bad and #4 is affected also I'd say its gasket or a crack at this point. I'm looking to buy a bore scope soon to try and lessen a tear down.
A lot of the L67's crack between the valves and don't smoke. Pretty sure Scotty has some pics. I would check the valve guides you may have a super sloppy one that needs to have a new bronze guide pressed in or at least knurled. If it's sloppy as a few I have seen I wouldn't be suprised by the smoking at idle at all.
Its just weird that the two cylinders next to each other are doing this. They are Hinson ported heads and the guides were milled down I'm pretty sure to accept a larger lift in the future. Unsure how he does this but if they are leaking it sounds like the head must come off no matter what , then be sent out to a machine shop to have everything checked.
Well, there's some dubious things that seem to go on his heads. There is a pic in one of the threads and the valve guide is literally oblong. I don't know, I have heard that he did the port work and the customer had the machine work done and it was the machine shops fault. I don't know who I believe, but there have been several people with issues with them. Again I don't know who's to blame, but I would check the valve guides for wear. Just rock them around and see what you get, they shouldn't really move at all especially with the springs in place. Again the cracks between the intake and exhaust valve seem to be normal and lots of people run them as is and don't have any issues.
http://www.grandprixforums.net/threa...ghlight=hinson
Post #148 shows what I think the issue could be.
Jeff
I'm pretty sure the plugs I pulled out of the heads 2 plus years ago were not white. I know for a fact I got one of my heads back along with a different head that I did not send in. As I cleaned the bottoms very well. So I knew I got back at least one of my originals. I did call him out on why did you not send them back as a pair as the ones I sent. I believe he said he already had 1 ready to go.
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