AC WD45 Standard Piston

[Clem McNure]

I have a wd45 which had stuck pistons in the engine. I removed them but two of them where pitted real bad andI need to replace them. It has standard 4 inch aluminum pistons with a deep dish in them. I can find replacements but the pistons are either flat top or has a concave top but not like the ones I removed. I was wondering if these can be used as long as I change all four out to be the same ?
 

[JMS/.MN]

Flat tops were standard in the WD. Original WD45 concave was the 'Power Crater' piston. Gave increased hp and better combustion. Should be no problem as long as all four are identical.
 

[BushogPapa]

Buy a complete Kit: Sleeves, Pistons, Rings, gaskets, Etc...

Might as well get a 4 1/8" Higher compression kit..costs the same, anyway..

I put a "Gas" D-17 kit in mine..7.4:1 Compression..Never had any problem..

Clean-out the water-Jacket out well and coat the bottom of it liberally with Non-Hardening Permatex.. Use the same Permatex, when installing the Sleeves...

I had already changed to 12V and Alternator..
6V would start it, but never would "Spin it over"..just turned one-cylinder-at-a-time...
Get a GOOD Valve Job done and increase the seat pressure of the Valve Springs..
While the engine is out...replace the engine clutch and be sure it has a 9 spring pressure plate..
Do these and she will stand Blue Flame and work with the front wheels off the ground in 2nd gear..

Ron..
 

[Jerry Coulter]

The WD45 crankshaft has a longer stroke than the WD. Don't use flat top pistons with the long stroke crank unless you are building a puller tractor.