[briansansone]

Hello .. First message board posting . I am having major problems installing pistons with new rings in my 88 chevy 350 . All gaps are within specs , machine shop said pistons look good , rings are cast iron from napa , rings are on correctly ( i paid close attention to markings and directions ) piston was placed in the original orientation ( mark towards the front) all pistons slide freely in there cylinders with no wooble( without rings ) , I coated the piston and bore with plenty of oil , and now the piston is completely jammed in the cyllinder ??? I tried the next piston and it also jammed . I used a somewhat flimsy ring compressor for the installation . Could this have caused a problem ? What am i missing? I have never had this kind of problem . All my previous engine rebuilds were water cooled VWs . This is my first push rod V8 .

 

[meanroy]

Engine problem

Hi Brian, welcome to the board.
First, you should post this in the engine section, maybe one of the mods will move it for you.

.. All gaps are within specs , ...

Did you put the rings into the cylinder and measure the gap with a feeler ga?

... the piston is completely jammed in the cyllinder ???

How far down the cylinder does the piston go before jamming? past the first ring, 2nd ring, etc. ?

Are you positive the rod isn't coming into contact with the crank? You can make some ugly nicks that way and have to turn the crank to fix it. I usually put pieces of tubing over the rod bolts just to be safe.

This is my first push rod V8 . [/B]

Just pay attention to detail and you'll be ok.

Roy.

 

[briansansone]

Hello from brian . I found the problem . It took trips to all the major auto parts stores , two chevy dealerships and two machine shops to finally get an answere . From 1987 to 1995 chevrolet made two distinct pistons: deep oil groove pistons and shallow oil groove pistons . My truck was equipt with the shallow pistons . The shallow groove piston ring set is apparently hard to find . Not even did the chevy dealer's parts and service department know about this distinction . I finally found a knowlegeable machine shop who ordered the correct rings. MR GOODWRENCH ?? .

Now I have a new issue . I scarred up two rods trying to remove the jammed pistons , and instaed of having them remachined the machine shop put my pistons on some used 350 rods that were laying around ( for free ) . Later when I got home I realized that one piston was on the rod reverse of all the others , and the two foreign rods had the counter ballances shaved down . Will I have a severe balance problem ? can I reverse the backwards rod to maintain the original piston orientation ( mark towards the front ) ?

 

[troy-curt]

You will have to refit the piston. The rods have a thrust side that has to go to the crank side. If that makes scence.

Troy