Vertex ring end gap/upper rod bearings. 1983 chrysler 90 4cyl.

[healey8390]

Finally got my block back after 1.5 months at the machine shop. To his credit got two pistons, a bore, three hones, gasket set two upper bearings and a block deck for $300. Guy got me vertex pistons but there are no instructions for end gap. On their site they say their rings fit oe pistons so does that mean i use oe ring gap? My chrysler book says .006 to .016. Secondly, The upper bearing set seems like it fits funny to me, the washers are not flush against the sides like the oe press style there is a gap. If i let everything slide to one side theres a gap about 3/16. I checkd pro marines site and it says must use wp29-1 (has a note that wp29-1 is same as wiseco w5216) wrist bearings and thats what he gave me but seems kind of sloppy to me.

 

[Frank Acampora]

Re: Vertex ring end gap/upper rod bearings. 1983 chrysler 90 4cyl.

Use the manual ring gap specifications. Ring end gap is set to allow for expansion of the rings, not the piston. Don't worry if the gap is a little more than factory specs though. They will only leak a very small amount more unless it is really excessive. Too little end gap, however, will result in the rings jamming in the cylinder so that needs to be corrected.

The bearing keepers are there to prevent the small end needles from slipping down out of the rod small end too far, thereby limiting the area of the needles in contact with the rod. Since the crank cheeks keep the rod itself from moving more than a couple of thousands of an inch, a little slop in the needles is acceptable. 3/16 does seem excessive though. However, if 90% or more of the needle's length is in contact with the rod small end when the rod is centered in the piston and the needles are pushed as far to one side as possible, then there is no problem.

 

[healey8390]

Re: Vertex ring end gap/upper rod bearings. 1983 chrysler 90 4cyl.

My ring gaps are as follows: #1 .019,.02,.02 (new rings). #2 .015, .016 (new piston and rings .02 over). #3 .014, .016, .016 (new rings). #4 .019, .021 (new piston and rings std). As far as the wrist pin spacers are concered, i measured the gap better, coincidentally the body of a qtip fits perfect and i miced it and its .1 ( thats last time I eyeball something lol) so mabye its not as bad as i thought just thought they should be flush and thought it might make noise. I know you use wisecos alot Frank do they have a small space too? Thanks!!!