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Sat May 19, 2012 1:12 pm

Well I started out real excited about this weekend & driving my 356. Rolled it out of the garage & went to start it. Cranked for a few seconds a then a loud bang. Firgure I broke the starter gear or something. Then it just spun over with what I thought was the starter not engaging. Pulled the starter found the solenoid was loose on the starter so I tightened it & checked the teeth & the flywheel teeth. All looked good reinstalled the starter & same thing. Had my son crank it while I looked from the bottom & to my horror the starter engaged & the flywheel turned. So up top I go and had him crank it again. Wow the pulley isn't turning. I'm really bummed now. Can't think of anything else but the crank broke. What are the chances the flywheel bolts broke. I'm disgusted right now. I'll pull the sump later & post what I find.

Sat May 19, 2012 1:14 pm

Try putting the car in gear and see if you turn the pulley with a wrench.

I feel your pain.

Sat May 19, 2012 1:16 pm

Crappy news. Hopefully its not the crank itself.

Sat May 19, 2012 4:40 pm

MMW wrote: Well I started out real excited about this weekend & driving my 356. Rolled it out of the garage & went to start it. Cranked for a few seconds a then a loud bang. Firgure I broke the starter gear or something. Then it just spun over with what I thought was the starter not engaging. Pulled the starter found the solenoid was loose on the starter so I tightened it & checked the teeth & the flywheel teeth. All looked good reinstalled the starter & same thing. Had my son crank it while I looked from the bottom & to my horror the starter engaged & the flywheel turned. So up top I go and had him crank it again. Wow the pulley isn't turning. I'm really bummed now. Can't think of anything else but the crank broke. What are the chances the flywheel bolts broke. I'm disgusted right now. I'll pull the sump later & post what I find.
I have seen a few instances of all 8 flywheel dowel pins sheared off due to "hydro lock", that is, one or more cylinders filling with fuel. This situation will suddenly stop the engine, very suddenly, resulting in undue stress being applied to the flywheel/crankshaft interface. The dowel pins are an interference fit to the crankshaft and very difficult to remove without damage to the pin bores. I have sent a few complete engines to Jerry's Tap and Drill http://www.brokentap.com/ for broken pin removal with excellent results. Stoddard's has factory pins for sale (#9) http://www.stoddard.com/shop/shopdisplayproducts.asp?id=26&cat=Crankshaft+Parts. Scat crankshaft has replacement pins of their own manufacture that are appox .001" larger than the factory pins that they use in 356 crankshafts that they make, if the bores have been stretched. These replacement pins are slightly longer than factory pins, so some grinding may be needed to keep them from protruding beyond the thickness of the flywheel. If more than 2 are loose, be careful! The flywheel generally take the brunt of the damage to the pin bores, but if they are OK, the mating surface can be resurfaced. Otherwise, a replacement flywheel will have to be found. This solution will likely effect end play, so a different shim will be required to stay in acceptable tolerance. If particular attention is not paid to this area, you will be facing even more damage to this problem area.
I don't recognize MMW, so it would be nice to know who I am speaking to.
Thanks,
Jack Staggs

Sat May 19, 2012 5:42 pm

(I don't recognize MMW, so it would be nice to know who I am speaking to.)

I've added my name to my signature.

Thanks Jack & everyone for the info provided. Going to pull the sump plate off & have a look inside tonight. I am very new to working on these engines. Somewhere in my teens I went off to street bikes & small block chevys. Now I have this so I need to learn. Just a major disapointment that I have to pull the motor as I don't really have a lot of time & the weather is starting to get nice.

Sat May 19, 2012 7:43 pm

O/k so I dropped the sump cover & it all looks good. Hard to see through the cam but had my son turning the pully side of the crank & it all looked fine. Oil was clean & so was the inside. I'm now leaning towards broken dowel pins as Jack has suggested. I will pull the motor as I get time. How far back does the motor need to go before dropping it out the bottom? Once out anything special I need to know about pulling the flywheel? Thanks again.

Been reading up a little bit & I see all that holds it on is one nut. Right hand thread, correct? Hoping this is it.

Sun May 20, 2012 5:45 am

I got a 912 motor in a few years back that had all the pins sheared off, so it can be done. This guy had let his girlfriend drive while he slept, she missed a shift, bad, and that was the end of the weekend getaway.
But here is the funny part the engine was in his basement, where it had been sitting since the mid 70s. Except he keeps insisting the engine has new rings and the top end was re-built, in 1973, and the engine has been locked up since who knows how long.
He tells me he wants $1200. I say so thanks, he asks me how much, I say $700, he says, "NO!" His wife says, "Take the money." He raises his hand and says, "Upstairs, Woman!" At this point it is getting really weird and so we make a polite exit out the basement door. I get to my truck and my phone rings, it is the wife. She comes out and says, "Give me the $700 and I will add $500, that way everyone is happy."
So I get back down to the basement and the guy now has $1200 in his hand and a big shit eating grin looking at me like I paid the price, that's right!
We took the engine, but wow, what a strange day.

Sun May 20, 2012 6:17 am

Mic, you will need to remove the dipstick and the horizontal sheet metal engine shroud (this one http://www.thesamba.com/vw/classifieds/detail.php?id=1274347 [borrowed photo]) above the muffler to pull the engine back far enough for removal. Don't forget to disconnect the tach cable. Get one of these http://www.thesamba.com/vw/classifieds/search.php?...wheel+lock and a 36mm or 1 7/16 socket. The nut is recessed so you may have to grind down the O/D to get full purchase. The nut is supposed to be tightened to over 400 ft lbs. Right hand thread.
PS.Adam, smart wife!

Mon May 21, 2012 6:49 am

Unobtanium-inc wrote: I got a 912 motor in a few years back that had all the pins sheared off, so it can be done. This guy had let his girlfriend drive while he slept, she missed a shift, bad, and that was the end of the weekend getaway.
But here is the funny part the engine was in his basement, where it had been sitting since the mid 70s. Except he keeps insisting the engine has new rings and the top end was re-built, in 1973, and the engine has been locked up since who knows how long.
He tells me he wants $1200. I say so thanks, he asks me how much, I say $700, he says, "NO!" His wife says, "Take the money." He raises his hand and says, "Upstairs, Woman!" At this point it is getting really weird and so we make a polite exit out the basement door. I get to my truck and my phone rings, it is the wife. She comes out and says, "Give me the $700 and I will add $500, that way everyone is happy."
So I get back down to the basement and the guy now has $1200 in his hand and a big shit eating grin looking at me like I paid the price, that's right!
We took the engine, but wow, what a strange day.

Hilarious!

Tue May 22, 2012 6:10 pm

Got it apart & the dowel pins are broken. The gland nut wasn't as tight as it should of been. Not sure if that was the cause or it loosened when the pins sheared. The pins are an interference fit right? Any ideas on how to remove without disassembly & shipping the crank out? I'll make some inquiries locally. I do know enough not to let just anyone try it.

Now I'll have to figure out why they broke. It did sound like it hydro-locked when I tried to start it. So maybe the a carb is leaking down? I don't want to put it together & have it happen again.

Jack -- Unfortunatly I am on the east coast so shipping the engine to Jerry's drill & tap removal is not going to work but maybe I can find a similar company here. How do you remove good pins, a slide hammer? I was thinking of tigging a washer onto each pin & a nut onto the washer then attaching a slide hammer. But if they are a press fit vs. interference that probably wouldn't work.

Tue May 22, 2012 6:33 pm

Looks like a clean break.

Maybe can drill a hole in each and use a ez-out or something to grab them.

Only a suggestion.

Tue May 22, 2012 9:04 pm

I'd be tempted to weld a stud onto the pin and use a puller or slide hammer. You could probably tig the stud on as you said or use a stud welder
http://www.eastwood.com/stud-welder-dent-pulling-system.html.

Tue May 22, 2012 9:31 pm

Long long long time 356 experience tells me you gonna be best served by taking the crank out.

Take it to the machine shop.

Loose gland nut may be bad threads too.

This is not a pleasant situation.

Do yourself a favor.

Do NOT fool around.

It can get worse later......

Tue May 22, 2012 10:15 pm

If you can remove the pins by any of the previous suggestions, they are likely not tight enough, and you will risk further damage to the crank during removal or another failure post repair. This is a very slippery slope! Believe me, I am not guessing here. Did you call Jerry's? They answer their phone. Email, I doubt. Perhaps they know someone closer to you.

Wed May 23, 2012 5:16 am

Thank you all for the advice so far. Please note that the gland nut wasn't loose like hand tight. It just wasn't as tight as it should of been. The threads in the crank look o/k at first inspection. I put my 1/2" impact on it & it didn't even struggle when removing it. It possibly could have loosened when it broke but I'll never know. I could spin the flywheel by hand once I had the engine out.

Wed May 23, 2012 5:20 am

Jacks wrote: If you can remove the pins by any of the previous suggestions, they are likely not tight enough, and you will risk further damage to the crank during removal or another failure post repair. This is a very slippery slope! Believe me, I am not guessing here. Did you call Jerry's? They answer their phone. Email, I doubt. Perhaps they know someone closer to you.

So what your saying is they should be a press fit vs. interference fit? I'm sorry if it seems I'm asking stupid questions just trying to understand it all before I decide how to go about this. I truly do appreciate any & all suggestions. I got the name of a local guy who is supposed to know all about these. I'll stop in to see him soon.

Wed May 23, 2012 5:23 am

Glenn wrote: Looks like a clean break.

Maybe can drill a hole in each and use a ez-out or something to grab them.

Only a suggestion.

I assume they are hardened so I don't think drilling would work at least with my equipment which is a hand drill.

Wed May 23, 2012 6:35 am

http://en.wikipedia.org/wiki/Interference_fit

Wed May 23, 2012 7:38 am

I don't see what there is to lose trying to weld a pin to the end of the dowel. You'd have to let it cool before pulling and you might need some kind of hydraulic puller to get them out. Your other choice is to pull the crank and get them removed via EDM http://en.wikipedia.org/wiki/Electrical_discharge_machining. Years ago I did send out a few bits for EDM when no other method would work. These machines are not overly common and cost may be an issue vs replacement. You could always get a quote and make the call.

Wed May 23, 2012 8:17 am

I have a 912 crankshaft that has been lying on the floor of my shop for the last 20 years. The problem with it is that someone tried to weld on the dowel pins and bodged the snout of the crank. I haven't figured out how to fix it yet, so there it sits. Good quality new crankshafts are now over $2000, so that is the risk. The link that I gave in my 1st post, http://www.brokentap.com/ , is a company that has a fixture that allows them to remove these dowel pins with their EDM machine WITHOUT DISASSEMBLING the motor. Cost appox $300 and usually done the next day. Perhaps they know someone on the East Coast. Or weld. :D