Cam install possible disaster.... Please help PTV?

stupidslow02gt · May 10, 2008

I have an 02 GT and just finished putting in comp 270's with bee hive springs. I installed the cams without taking the timing chains off (just slid the gear off the end of the cam and swapped in the new cams) so that I didnt have to re-time the motor. The only thing that I didnt do was soak the lifters in oil before I reinstalled them.

I was wondering if you guys could offer me some advice and clear up a few questions for me. First of all, are the shafts left and right specific? Will they work on either side of the motor? Could I have installed the followers wrong? Is it most likely the lifters not pumping back up?

Also, I did not degree the cams. I did a lot of research and people told me to just install them straight up. I have a good buddy with a bullit and he installed them the same way I did. His motor was noisy for a few hours and then was fine and runs strong. My motor runs strong too, idles fine and doesnt miss or shake. I am just wondering what I missed. On Monday I am getting a borescope to take a look at the top of the pistons to see if they were nicked at all.

Here is a video (the video makes the knock sound way louder than it really is)

http://www.youtube.com/watch?v=CPy9MpEBRwA

ANY ADVICE IS WELCOME. Thank you.

joshjwc9 · May 10, 2008

That sounds like some PTV issue. It has been awhile since I helped a buddy do a PI swap on a 96 GT, and he had similar sounds....I wouldnt say it is that 100% but there is a good chance that it is...was this tuned or no?

stupidslow02gt · May 10, 2008

It was scheduled for a tune on Monday

hotstang_46 · May 10, 2008

I'm surprised you were able to slide the gear off the cams. When I was doing my heads I remember the stiffness of the chain not allowing much lateral movement. I have not ever done it the way you have, but only thing I can think of is that maybe you didn't keep constant pressure on the chain when swapping and it skipped a tooth down by the crankshaft throwing your marked link off when reinstalling

I'm sure others will chime in...

stupidslow02gt · May 10, 2008

We had to remove the chain tensioners to get the slack we need to slide the gears off the shafts. Thats another thing. Maybe we put the tensioners back in wrong and the chain is slapping around in there. I have also heard that sometimes the chain tensions dont pump back up right. And I am positive the chain didnt skip a tooth. We also rotated the motor over by hand about 10 times to check for contact, it was fine.

hotstang_46 · May 10, 2008

mmmmmm....I don't really think you could put those tensioners on wrong...

I know that right after my head job she was noisy for a little while....not like your buddies or anything though, it certainly wasn't hours....

how long have you run your car for?

btw....I din't soak my lifters or anything either after having bled them

I'm no expert....but if you turned the motor over and didn't have PTV the only way i can imagine you'd have it is if for some reason the chain skipped a tooth...which if installed properly I don't think is possible......even if you bled the tensioners and they didn't fill up with oil right away

stupidslow02gt · May 10, 2008

The motor has been run for over an hour now. We drive it around the block a few times trying to see if the lifters needed to pump up. It just seems that the noise isnt going away.... I am starting to believe more and more that I am having a PTV problem. What about the followers? Anyway to put those in wrong? Or could I have put the shafts on the wrongs side of the motor or something?

hotstang_46 · May 10, 2008

by shafts you mean camshafts? yes if memory serves they are specific....

but I can't imagine you installing them wrong and not having PTV when turning over by hand

stupidslow02gt · May 10, 2008

Well I guess I will know more when I start tearing it apart again. Ill probably look with the borescope first, then pull the valve covers.

hotstang_46 · May 10, 2008

sounds like you are covering your bases which is a very good thing. I'm sure others with some more knowledge will chime in.

Good Luck!

Jbauer · May 10, 2008

That sounds like a lifter problem to me. I remember Many cammed jettas making a very similar noise, and my cammed jetta also made a very similar sound to that too- just a bit quiter.

stupidslow02gt · May 11, 2008

Well what would prevent them from pumping back up? Should I just take them all back out and fill them with oil and then put them back in?

oxfordgt · May 11, 2008

You would know if you put the cams in the wrong side head by the $3000 price tag for a new motor.

1. You must always degree comp cams
2. That was the most retarded way of swapping the cams I have ever heard of
3. Timing (putting the chains back on) takes like 30sec tops why didn't you want to do it.

trinity_gt · May 11, 2008

I notice your engine sounds, apart from the distinctive knock, a bit like a diesel now. I've got Comp 262AHs in my 02 GT and get that same weird, diesel-like "timbre." I get no such knock though.

If in the process of taking things down you find the cause of that diesel-sound, please post back...

stupidslow02gt · May 11, 2008

I swapped in stage 2 cams without having to re-time my motor and you consider that retarded?

SonicStangGT · May 11, 2008

I just saw this and was thinking on what else it could be, did you locktite and torque the cam bolts, have heard that than can come loss if not, might cause your sound.

ooraceredgt · May 11, 2008

i just had my engine rebuilt with new cams and ported heads. the car hasn't been driven that much since the new engine but has been on the dyno. i noticed a knock very similar to that in my new engine. the knock seems to only come from the drivers side. everyone i have spoken too says its a lifter problem. if it is the lifter for me, just gonna replace the heads. let us know what you find out.

BobHyatt · May 11, 2008

PTV problems

stupidslow02gt said:
The motor has been run for over an hour now. We drive it around the block a few times trying to see if the lifters needed to pump up. It just seems that the noise isnt going away.... I am starting to believe more and more that I am having a PTV problem. What about the followers? Anyway to put those in wrong? Or could I have put the shafts on the wrongs side of the motor or something?

I don't believe you have this problem. If you could hear the valve hitting the piston, the most likely thing you will hear next is either a miss because the valve head bent to the side very slightly and will not seal when closed or else a follower off its cam lobe because the valve stem bent and prevents the valve from moving in the guide (which is also probably damaged, been there, done that, got the T-shirt).

I'd check the chain to see if it is tight (and I do mean tight, not flopping). I have seen lifters lash adjusters make a lot of racket but only for a few seconds, not hours...

Good luck, but if you turned it over to make sure there was no interference, that should not be giving you issues. Would be nice to run it with valve cover off but that will sling oil all over heck. You could find a borescope and look down thru the sparkplug holes to see if you see any marks on the piston. The contact usually comes at about 4:00-5:00 position and is visible on the corner where the dished center rises up to the top edge of the piston. The mark(s) will be quite noticable if that is the issue.

The piston tops are dished, but not in the right place for improved valve-to-piston clearance, it is more of a "lower the compression ratio" issue. Would have been nice had they flycut the pistons to start with, but that's another story...

You could possibly put a follower on backward, but that is about the only choice. One end has a rounded pocket to fit the lash adjuster. The other is flat to match the end of the valve stem. Should you get that backward you might get some noise if it will actually install that way (I have never tried to install one backward so have no idea if it will even fit).

BobHyatt · May 11, 2008

stupidslow02gt said:
Well what would prevent them from pumping back up? Should I just take them all back out and fill them with oil and then put them back in?

If you have oil in the motor, they will pump up naturally, although it will take a few seconds for all the tapping to go away...

stupidslow02gt · May 11, 2008

Just talked to a reputable engine builder and it has pretty much been determined that my intake valves are hitting the pistons. He said there is really no way of degreeing cams in a 2v motor because everytime you go back to re check your work the numbers are always off. He just installs them straight up and notches the pistons every single time. So his best advice is to run the motor pull the heads and take a dremel and finish notching the pistons where the valves left off. Then replace the valves and drive the car around. He said that there is no way to put in a comp cam in a 2v motor without the vlaves kissing the pistons, even the 262's. This is ESPECIALLY true on the non-pi motors that have flat top pistons.

Cam install possible disaster.... Please help PTV?

New Member

Active Member

New Member

Member

New Member

Member

New Member

Member

New Member

Member

New Member

New Member

Member

New Member

Active Member

New Member

New Member

New Member

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency