Engine Back In. Won't Start. Help!

[VaSteve]

After a long day of reinstallation (Thanks Bill & Barb!!) the engine is back in, bolted up, oiled, etc. etc.

But it won't start.

It cranks fine. But won't turn over.

I cranked it several times and kept setting off the pop-off valve.

I stopped after three times. I can assume that I am getting fuel and spark (from popping the airbox). Ring gear is on, because the first time I cranked it (in gear) it jumped. What else could it be?

Yes battery has been sitting in the car for 2 months while the engine was out. Could it be weak? If we take the battery out of the equasion, what else should I check.

Thanks, Steve

[ianc]

Any sign of a fire at all? Plug wires not crossed? Fuel pump running?

ianc

[Jim Sims]

Cranks fine, but won't turn over? You mean it won't fire? Check sparkplug wire order on distributor cap.

[VaSteve]

Checked spark plugs wires. They appear to be in the correct order. Someone told me to check the distributor since I pulled it out. I will do that.

One more variable, I backdated the heat and my #2 plug wire is close to the metal (of course it's shielded by the rubber plug wire boot). That shouldn't cause a problem should it?

[jim912928]

If you pulled the distributer it could reinstalled wrong...it's possible you have it off by 180 degrees. If you are getting fuel, and if you are getting spark (did you check this at the plug wire?) then it's probably timing...check that distributer!

[creaturecat]

hand crank to top dead center - firing #1 cyl - pull the cap - ensure that the rotor is where it is supposed to be. good luck

[crashmy911]

Yeah make sure you are getting fuel. how long was it sitting fuel pumps have a way of going bad when sitting. Also make sure the battery is fully charged these old cars have a way of not starting when battery ins't up to snuff. At least this is what I find with my sc.

[Zeke]

It sure is easy to miss a wire when reinstalling a motor. Ask me how I know. Check 'em all again. You'll most likely find something real simple is holding up the show.

[Wayne 962]

99.9% of the time when the engine won't start after being out, it's because the wires are installed correctly, and/or the distributor is on backwards.

Check it, check it again, then go have lunch, then check it one more time. I have checked this twice in the past, only to find the third check that I missed something.

Remember 911SC & 1978-89 Turbos run counter-clockwise.

-Wayne

[crashmy911]

Make sure your ground strap is making a good ground mine always goes bad for some reason. After I clean it up my car will start. So make sure that is good too.

[David]

If you're using the Bentley manual, check your plug wire order from another source.

[VaSteve]

The results thius far....

1. Checked the alignment of the the rotor when Z1 is at TDC. It was off.
2. Tried again. Kaboom! (See photo)
3. Spoke to Charlie who's highly knowledgable and said that the distributor was probably off 180 degrees.
4. Removed left valve cover and found that he was right. D'oh!

I'm off to Pep Boys from some epoxy to complete Project #32.

(In addition, I found a way to not press the rotor all the way down onto the peg and still get the cap back on. Double d'oh!)

[William Miller]

Sorry, I missed this. Next time call me!
Remember I said it looked like it might be off a tooth?
Obviously a lot more.
I'll stay posted to see the good news!
Good luck!

[Christien]

Steve, did you by any chance have any gas leaking out when you had this starting problem?

[ruf-porsche]

If the pop off valve blew out of the airbox, I would check the air box for cracks. The popoff valve is suppose to open in the event of a backfire, not blow out.

[VaSteve]

Originally posted by Christien
Steve, did you by any chance have any gas leaking out when you had this starting problem?

Nope. It was all because I had the distributor in backwards.

Ruf: The airbox is fine (fortunataly!) I had it at the track last weekend and it ran great!

[ruf-porsche]

Originally posted by VaSteve
Ruf: The airbox is fine (fortunataly!) I had it at the track last weekend and it ran great!

I thought the popoff valve blew up when you had the timing off by 180 degrees. Was this before the track event? If it was after the track event your air box could have been damage when your engine backfire and blew the popoff valve out of the airbox.

[Paul Valcourt]

Everybody uses epoxy and if there is a major backfire the pop-off is loosened or after a few years in the engine compartment the epoxy will get brittle and allows leaks. If you use urethane then these problems would not happen. Anyway good luck with the project I hope you get it on the road soon. I am about to put mine into mothballs and just ride my bike for the summer.

[VaSteve]

Originally posted by ruf-porsche
I thought the popoff valve blew up when you had the timing off by 180 degrees. Was this before the track event? If it was after the track event your air box could have been damage when your engine backfire and blew the popoff valve out of the airbox.

Sorry. I should have been more specific. The pop off kept going off when the distributor was out of whack 180 degrees. After about 5 pops the glue gave out and and I had to re-expoxy it (bonus, it was previously in backwards).

That was at the end of February.

Last weekend was the track event. It's all good now.

[Wayne 962]

Originally posted by Wayne at Pelican Parts
99.9% of the time when the engine won't start after being out, it's because the wires are installed correctly, and/or the distributor is on backwards.

Check it, check it again, then go have lunch, then check it one more time. I have checked this twice in the past, only to find the third check that I missed something.

Remember 911SC & 1978-89 Turbos run counter-clockwise.

-Wayne

Add another data point. Okay, now it's 99.95% of the time.

-Wayne