piston slap??video

[russell3123]

I did not clean them, I figured I didn't have to they were brand new. I pumped them with oilthen drained them and put them in.after I took out the mpi relay and turned the car over a few times for 10 seconds then fired it up, it ran for about 20 minutes then back fired.

 

[jimbob_843]

Man... So no signs of a cause? Guess it was just its time to go. Sorry to hear that.

 

[russell3123]

Only thing I can think of is I didn't get at the metal shaving out from when the owner before me fried apiston.

Hey I have two Ross. 020 piston, I was thinking of swapping my one blown Manley piston. Has enyone ever tried something like this or is the weight difference to much?

 

[BogusSVO]

That depends if they are the same CR.

I would have the pistions weight matched tho

 

[russell3123]

I did not think of that. Im pretty sure the manleys i have are 9:1 and the ross are 8.8:1.

 

[BogusSVO]

If that is the case, I would order one manley replacement piston....

Then have all 4 pistons weight matched.

http://www.dsmtuners.com/forums/cylinder-head-short-block/342138-how-fix-balance-hang-pistons.html

It is a bit of a pain, but worth the effort, it will help the engine run smoother.

 

[russell3123]

Do you know anyone that sells them individual?

 

[BogusSVO]

Pull the part nimber from the top of the piston, if you do not have it somewhere else.

Then check with one of the supporting vendors! Extream PSI, JNZ or one of the many others and see who can get you one!

 

[jimbob_843]

Started to pull my head today. Got cover, belts, and pulleys off and noticed my intake cam gear has a little play. Side to side, almost as if the dowel is bent or too small. Will this cause a sound like the video posted? Proceeding with the pull tomorrow.

 

[BogusSVO]

Cam gear bolt not torqued right?

That tad bit of play will not cause what you have discribed, but needs to be taken care of.

did you see any followers off the HLA/valve tip

 

[jimbob_843]

Nope everything is still intact, nothing loose or damaged. Will see valves tomorrow if i can get off before dark.

 

[jimbob_843]

Ok...so i pulled the head today. Everything looked very nice. I still plan to port the oil feed. The galley wasnt very deep at all. I took the lifters and rollers out to test the valves. With head upside down and sparkplugs in, i filled the cc's with kerosene. One exhaust valve leaked right away. And 5 min later 2 intake valves leaked. Im not very experienced with valves yet but im certain this would not cause a noise like the op's. I didnt see any damage to the valves so im gonna lap them and see where it goes. Any advice on the grit compound to use bogus?

 

[BogusSVO]

Jimbon.. I use permatex fine

http://www.dsmtuners.com/forums/articles-engine-fuel/341636-how-lap-valve.html

 

[jimbob_843]

Appreciate it sir! I picked up some permatex valve grinding compound in a tube for a couple bucks. Im gonna take it from here ill post up ifi have any problems.

 

[BogusSVO]

Ok cool..... If you need more help look here

http://www.dsmtuners.com/forums/cylinder-head-short-block/420045-how-have-4g63-head-rebuilt.html

Post #17 has links to all the "how tos" and tech on the 4g head I have written.

 

[jimbob_843]

Appreciate it! And thank you sir for all of your imformational write-ups!!! Without them most of us would be lost!

BOGUS IS THE MAN

 

[russell3123]

I agree bogus is the man.I should have my head off tonight and will be posting some pictures .

Finally got the head of in record time , only took about 50 minutes. I broke three valves and put a huge hole in cylinder three. sorry you need to right click on the picture and open in new window, i cant get them to work right. Or you can look at my uploaded pictures.

 

[jimbob_843]

Dude! Sorry for your loss. Mine actuallly turned out to be a bent valve. The 2 slow leaking exhaust valves lapped up fine. The one fast leaking intake however did not want to come out! No damage to the seat or the guide! Lucky i guess.. it was caused by a siezed or improperly primed lifter from my previous build. When i pulled the vc awhile ago the roller was off of the lifter and valve. The car ran with only 7 intake valves , how? Idk noob mistake and was never discovered until the teardown.

Bogus..
If i buy a new replacement valve will it be a direct lapping and fit? Or will the seat and or valve need to be cut/sized?