gideonstyle

So I have a 91 Rx7 GTU engine that I pulled out to be rebuilt (had blown coolant seal). So a friend of mine that has built a number of rotatry engines, put the engine together last night, while I kinda helped a little lol.

But anyway, after we finished assembling the engine, we could not rotate the engine with a ratchet. After we loosened all those bolts that go through the back (behind the flywheel), the engine actually will spin properly.

My only guess is that one of the iron "faces" is warped enough to where it's binding a side seal on one of the rotors. Any ideas?

TrboSpdAnt

iTrader: (5)

POssible. Could be that the rear iron's face is warped, quite abit.... Make sure you don't have any extra bits, layin' around; never know - you could have left out a spacer, or something.

THansenite

Could the torrington (sp?) bearing have fallen and jammed the e-shaft when you tightened the front bolt?

TrboSpdAnt

iTrader: (5)

That wouldn't've seized the engine, though.... NTM if the engine was apart, on it's ***, then it should've been held in place by gravity.

There isn't any way to tell unless you yank it BACK apart, stating your inspection with the rear iron, since that's where you've determined that the starting issue lay....

Did you guys try rotating it, by hand, while it was on the stand, or in the car?

K-Tune

iTrader: (26)

take the motor apart and investigate. was the engine ported? why was the engine rebuilt?

you can measure warpage with a straight edge and feeler, which should have been done before the motor was put together.

RotaryEvolution

iTrader: (30)

engine needs to come back apart, something probably slipped out while assembling the engine. for example, for the first time in about 120 engines or so i had an apex seal boot pop out while replacing a rear iron and it got caught right between the rotor housing and iron.. i was rather upset at such an irritating issue to say the least, mainly because i had to eat a rotor housing on that one. even the most experienced builders have something that happens now and then no matter how careful you are.

i have yet to see an iron warped enough to cause a binding issue(even on engines that have reached 300*F+ that liquified coolant seals), rule that one out.

gideonstyle

wow, thanx for all of the input everyone. Well, the engine ran fine before it was pulled apart, but it had a blown coolant seal in the front housing. So we pulled it apart and just cleaned everything before putting it back together.

The odd thing is that the engine rotates fine "assembled" until you tighten down the rear 16 or so bolts that go through all the housings. So since it rotates fine, I don't think that there's something like an apex seal that's popping out. So when everything is tightend up, it doesn't turn anymore, which leads me to believe a side seal is binding somehow. Makes no sense to me how a face of an iron could be that warped, so I would def say you're right, and plus they all looked fine anyway.

Well guess we'll take it back apart and measure the iron faces or see if there was something we did. I'll let you guys know what I find, might not be till this weekend tho.