SR20DET swap first start problems

Problems, ideas and comments specific to engine swaps.
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Ottawa510
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Re: SR20DET swap first start problems

Postby Ottawa510 » 02 Jun 2014 10:30

Definitely better the trans than the engine. I'm going to pull the trans tonight and see what's up. Thanks guys!

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Ottawa510
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Re: SR20DET swap first start problems

Postby Ottawa510 » 15 Jun 2014 06:51

To provide an update, we loosened the bell housing and turned the engine over by hand, while wiggling the bell housing around. The gear meshed (which hadn't been the case before) and we tightened the bell housing together. Now the starter turns the engine, albeit very slowly, and the gears of the transmission. In fact, the rear wheels move in gear. But it is still turning over very slowly, and it turns over much faster when the bell housing is loosened a little (1/8"). I am checking for spark and trying to fire up the engine with the bell housing a little loose. Any ideas what might be causing the high friction when the bell housing is bolted tight, but released when the bell housing is backed off slightly?

Thanks

2DoorJim
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Re: SR20DET swap first start problems

Postby 2DoorJim » 15 Jun 2014 08:29

Have you pulled the rubber gromet out from around the release fork and looked inside? You should be able to get a little bit of a view of what's going on. A fibre optic scope would help if you can borrow one.

Did you install any replacement clutch parts, release bearing etc or are they all original parts?

Are you sure you don't have the clutch disk installed backwards?

Was your clutch release fork engaged correctly on the release bearing?

When your bell housing bolts were tight, could you slide the release bearing back and forth (have to remove the clutch slave to do this). If you could side the release bearing this would negate the release bearing from being the issue.

Still thinking here...


edit: I believe you said your clutch did work correctly when you pushed the pedal down, if so this would negate the disk being in backwards. I'm not certain about the SR clearances but some vehicles have a longer snout on the splines on one side of the disk which can collide with pilot bearing etc which cause clutch release issues.

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Ottawa510
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Re: SR20DET swap first start problems

Postby Ottawa510 » 15 Jun 2014 12:41

Hi Jim, thanks for the suggestions. I will pull the engine and tranny and separate them and see what exactly is in there. When we first installed it there was an aftermarket clutch in there but we didn't remove/replace it, just separated bellhousing and engine apart to have a look, and later mated them again.

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bertvorgon
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Re: SR20DET swap first start problems

Postby bertvorgon » 15 Jun 2014 13:06

Is it at all possible that the plunge depth of the tranny input shaft into the pilot bearing is either too tight or bottoming out?
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spriso
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Re: SR20DET swap first start problems

Postby spriso » 15 Jun 2014 17:05

I did some phone diagnostic work with a guy who had a similar problem to what you had-- same thing, he could not turn over the engine for the life of him. We finally figured out that he had put the wrong bolts in the slave cylinder on the transmission and had locked down the clutch/flywheel with the overly-long bolts-- might be something to look at.

-m
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Spriso Motorsports
www.spriso.com

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Ottawa510
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Re: SR20DET swap first start problems

Postby Ottawa510 » 16 Jun 2014 04:06

Slave cylinder of the transmission - is that part of the bell housing or do you mean the clutch slave? If it's part of the bell housing, which part? We are using the factory bolts (that came with engine) but guessed where they went in based on length and diameter. The clutch slave bolts are the SR20 factory bolts.

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Re: SR20DET swap first start problems

Postby okayfine » 16 Jun 2014 06:19

Ottawa510 wrote:Now the starter turns the engine, albeit very slowly, and the gears of the transmission. In fact, the rear wheels move in gear.


Trans is in neutral for this, and the wheels still turn?

Ottawa510 wrote:I am checking for spark and trying to fire up the engine with the bell housing a little loose.


I would definitely NOT try to fire the engine until you've figure out the cause. Especially if there's some sort of binding at the trans and the trans isn't solidly bolted to the engine if/when the engine does fire, that could be some bad news.

I think your only realistic option at this point is to pull the trans. Inspect/remove/reinstall the clutch assembly, inspect the rest of the parts (fork, bearing, carrier), and look for witness marks that would indicate where it might be binding. Spin the engine with the clutch removed, and with the clutch installed. Unless the engine is supported properly I wouldn't attempt to fire it at this point. If all that checks out, look at the trans. In neutral, you should be able to turn the input shaft freely. You should also be able to turn it when in gear - it's how people figure out what trans ratios they have when they don't already know, by counting revolutions of the output shaft.

You should probably find the problem in all that, but if not then I'd take the front bellhousing off the trans and see what you can see.
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Ottawa510
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Re: SR20DET swap first start problems

Postby Ottawa510 » 19 Jun 2014 20:19

I pulled the engine and cannot separate the bell housing from the engine. I had a couple of friends (one of whom is skilled in engine swaps) and we were unable to separate the two. Unfortunately, I have run out of time for this swap as we are moving to California in a few weeks. So I will have to part out the car and parts. Unfortunate, but thanks for the help 510Realm! It's been a fun journey!

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andrew.lori
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Re: SR20DET swap first start problems

Postby andrew.lori » 20 Jun 2014 08:13

Something tells me the Clutch spline didn't line up so the clutch disk is stuck on the shaft. Never seen this happen before

Andrew
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