question re: valve train noises that dont seem normal.
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
few more things i did:
I checked lifter preload on a few more valves. I let it bleed down for about 15 mines, put that lifter on the base circle of cam and zero'd the dial. I am getting .100-.120 of preload on those two. So it seems the lifter is almost completely bottomed out. Hopefully the 7.350" pushrods i ordered will help some.
i also checked compression:
cyl
FRONT OF CAR
1 2
3 4
5 6
7 8
REAR OF CAR
1 222
2 235
3 220
4 240
5 200
6 215
7 202
8 237
Leakdown is next.
Dave
I checked lifter preload on a few more valves. I let it bleed down for about 15 mines, put that lifter on the base circle of cam and zero'd the dial. I am getting .100-.120 of preload on those two. So it seems the lifter is almost completely bottomed out. Hopefully the 7.350" pushrods i ordered will help some.
i also checked compression:
cyl
FRONT OF CAR
1 2
3 4
5 6
7 8
REAR OF CAR
1 222
2 235
3 220
4 240
5 200
6 215
7 202
8 237
Leakdown is next.
Dave
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
Here are pics of my opened up filter after about 140 miles. The flakes appear to be aluminum as they dont seem to be magnetic:
This abnormal for a new head/cam setup?
Dave
This abnormal for a new head/cam setup?
Dave
Last edited by TT_Vert; Jul 7, 2005 at 02:04 AM.
Chaulk up one more with a rod nock noise - very interested what you find. I just installed 7.35's and the valvetrain sounds smoother, but the noise is still there???
Just FYI:
I am running milled heads with TTP V.3 cam - Dual Springs - Stock rockers - New stock lifters.
Just FYI:
I am running milled heads with TTP V.3 cam - Dual Springs - Stock rockers - New stock lifters.
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Verdad Gallardo Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
well i got a head off and everything looks fine. The cam looks brand new, no lifters could be pressed in at all w/ my finger and there was no oil shavings or debris anywhere. I disassembled one lifter and plan to disassemble the rest as well. I have no p/v impact marks, the one valve ive checked so far is straight and its spring is ok. Before the night is up, ill disassemble both heads, check all springs and eyeball the valves for straightness the best i can. No news is bad news right now I hope to find something.
The only thing i noticed was i took the lifter valley off and while the cam gear is solidly mounted to the cam, the chain wil slide forward/back a slight bit on the gear. Im not sure if thats normal or not..
Dave
The only thing i noticed was i took the lifter valley off and while the cam gear is solidly mounted to the cam, the chain wil slide forward/back a slight bit on the gear. Im not sure if thats normal or not..
Dave
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
Whelp im fairly certain its a rod now. I took it apart, found nothing really so i reassembeld it. Decided to up the rev limiter to 7k. Figured if it was a rod it'll let me know now. Beat the hell out of it shifting around 6800. Man the thing feels awesome but the knock is still there. Now the oil pressue is as low as 20psi at idle and it'll sometimes fluctuate from 20 up to 25. I dont recall this from before nor do i recall having such a low oil pressure at 700 rpms.
This sucks..
Dave
This sucks..
Dave
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
i couldnt get one. What i did do was screw the compression fitting into the plug hole and set my regulator on the compressor to 100. Then let air into the cylinder. I only did this on one cylinder and it stayed around 98 or so. I did remove 4 valves and checked them fo straightness by spinning them in the guide. I only did a visual on the other 12 valves and springs.
Dave
Dave
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
boy this is odd. I started it this morning and drove it for about aminute before the noise came back. it seems to get loudest and begin at a lower rpm, the hotter the oil gets:
http://tech.cfbinc.com/dave/valvetrain2.avi
dave
Not that it matters now but im gonna do a leakdown here in a few (got a real tester)
Dave
http://tech.cfbinc.com/dave/valvetrain2.avi
dave
Not that it matters now but im gonna do a leakdown here in a few (got a real tester)
Dave
It's oil pressure related Dave. When your motor is cold, the pressure is higher and the oil is thicker. What you need is better pressure all the time. You probably don't have enough oil pressure to keep the lifters pumped up, thus the valve clatter. I'd start looking for the source of your low oil pressure. I think you'll find your problem there.
Good luck. Lord knows you could use some right now, LOL.
Good luck. Lord knows you could use some right now, LOL.
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
while i agree to a point. If it was oil pressure related the sound should be worst at lowest oil pressure (at idle). The fact of the matter is, it'll do it around 3k which i have about 40 psi. All that being said, 20 psi at idle would be more then enough to keep lifters pumped up i'd think. I was almost thinking that as the oil thins, the bearing to rod or crank clearance is loosening up and that is when the knock starts to occur. Also the oil pressure is lower due to the oil thinning and the looser tolerances of the bearing (s)
Dave
Dave
Last edited by TT_Vert; Jul 9, 2005 at 05:16 PM.
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
as a last hurrah i ran the car w/ the valve cover off. I put my stethoscope on the bolt the rocker is held on by and the bar that ties them all together and that seems to produce a sound almost identical. I put the stethoscope on the the surface by the pushrod and by the valve and its much quieter. What do you guys think?
Dave
Dave
Thread Starter
Joined: May 2004
Posts: 1,080
Likes: 0
From: Elgin, Illinois
yes but I have some good news i think. I bolted a rocer down and attached it to my vice. And i have some twisting movement in my rockers. It seems the rollar bearing fulcrums are somewhat loose on that part that the bolt goes through and acts as a pivot. I know the left to right sliding is normal but i dont see how the twisting plan can be normal. There is also some up/down play to them. If the center is stationary the actual rocker body can move up/down a tad.
Dave
Dave
Originally Posted by TT_Vert
as a last hurrah i ran the car w/ the valve cover off. I put my stethoscope on the bolt the rocker is held on by and the bar that ties them all together and that seems to produce a sound almost identical. I put the stethoscope on the the surface by the pushrod and by the valve and its much quieter. What do you guys think?
Dave
Dave
If you lost some needle bearing, you'll find them stuck to you magnetic drain plug
