Are FD eccentric shafts thicker than prior 13b models?
 

I'm puzzled. Today I recieved my parts as I was dealing with an endplay issue. Gadd another member who I can't thank enough has been helping iron out this issue. As a part of the process I ordered and recieved my thrust washer and needle bearing. When tearing the engine apart there are two needle bearings identical to each other, and two washers a thicker one that goes before the center plate, and a thinner one installed after the center plate which goes inside the counterweight. Well the parts turned out to be huge in comparison to the original thrust washer and needle bearing. They are about a 3/4 of an inch" bigger in diameter than the original ones. So either three things has happened.

One: I have a different eccentric shaft than a twin turbo motor, if there is a difference in girth between prior 13b, engines such as those found in 1986- 1992 rx-7's, and those found in FD's.

Two: mazda has changed out the sizes to a bigger thrust needle bearing and washer for who knows what reason. As the original fit snuggly around the eccentric shaft, but the bigger one fits snuggly around the inner lip of the stationary gear. I don't think this is plausible because both needle bearings are identical, and while the one fits snuggley in the inner lip of the stationary gear. It would be to big for the one that goes after the center plate.

Three: They ordered the wrong part perhaps off an rx-8 or something. But they swear up and down it is the right one.

13brew motors have larger thrust washer and the accompanying parts that go along with it. All 13b eccentric shafts are the same you can even use the early 84-85 gslse eccentric shafts on a 13brew motor. If your front stationary gear has the smaller thrust washer and bearings then someone changed them out. 1993 13brew came with larger thrust washers and the bearings to match the larger diameter thrust washer. You will want to use the larger set. If you have a Racing Beat performance catalog look in the engine internals tips it will explain everything. Good luck.

Thanks very much for time and assistance. That must be the case then. If so, they must have replaced the counterweight as well since it will only accept a smaller thrust washer.

So for my scenerio, then the front and rear needle bearings and washers will be of different diameter. And the larger diameter which is the ones I ordered will be the ones I want to use for the front the one that goes before the center plate, and into the stationary gear, and the smaller set I will use after the center plate with the washer inside the counterweight.

It was a Hayes motor I should have known better.

Ahhh shit, I was just thinking that the front washers are of different thickness between the two sets. Although the front fit, I don't know if it will work properly since one is different than the other. I mean litterly they are different thicknesses as well as diameter. The new set I ordered has a bigger diameter washer, yet thinner. The old ones originally installed have a smaller diameter washer, but are thicker than the new ones. Damn I'm all screwed. I'll probably have to order the set off the older models 86-92, just to keep it safe.

You know what sucks is that if they did that kind of switch around with the parts you might not have the FD stationary gears which are hardened and have the better main bearings. I can't believe a big name shop would do that. Sorry to hear about that.

I hate to hear it to. But there is plenty more that got switched around. But I don't want to give the company a bad wrap since the vehicle wasn't under my ownership when all this took place. For all I know the previous owner wanted a budget engine and got what he paid for.

I'm just stuck cleaning the mess up.