rebuild related questions-crankshafts

Greenmachine · Post by **Greenmachine** » Thu Apr 24, 2008 6:45 pm

Block enamel: Anyone find a nice green enamel that lasts? Almost no paint left on my block. Thought about 'au natural' but maybe rust could become a problem since it no longer wears a grease jacket.

Oil pump. Got two to chose from, both tight gears. One has the longer bolts so I was thinking it was probably the 30 mm as per another current thread on the board. Maybe a part No.?

The other one has a 'fin' at the end, looks like I could transfer it to the potentially better one. Any reason to/not to?

Thanks.

rallydiesel · Post by **rallydiesel** » Thu Apr 24, 2008 7:58 pm

Take apart both oil pumps and use the pump with the longer gears (height-wise). The plastic can and should be transfered to the pump you are using.

Greenmachine · Post by **Greenmachine** » Fri Apr 25, 2008 1:20 pm

Okay thanks, I'll keep the fin. It does make the pickup orifice smaller.

My next dilemma. I have these two crankshafts. I had to special order the new stretch bolt, but I just realized the shafts are different and the new bolt fits the old one I wasn't going to use because it had play.

Apparently the bolt I got is the only crankshaft stretch bolt available, the parts guy had another one listed that was discontinued. I'm guessing that's the one I need:

I can probably find a regular bolt to fit it but it won't be a stretch bolt. I wonder how critical the stretch is?

Post by **Fatmobile** » Sat Apr 26, 2008 12:53 am

The bolt on the left isn't a stretch bolt and can be reused if it looks good.
Came out of the early 11mm blocks.... might have been on some of the early 12mm headbolt blocks too, I'll find out when I remove the crankbolt on the car in my driveway.

ahistand · Post by **ahistand** » Wed Apr 30, 2008 10:19 pm

For the oil pump, you can just pull the two bolts out holding the halves together and measure the length of the gears to see what you have.

The real early pumps were 27mm, then in early '80s I believe they switched to 30mm pumps. As far as I know , both these had same pump body and therefore same length bolts. Not until the 36mm pump came out later in the '80s did the bolts get longer, because the pump body is actually longer as well.

Post by **Fatmobile** » Thu May 01, 2008 3:10 am

I think the Rabbits and stuff had the shorter bolts,... but even though the gears were 30mm in the Golfs and stuff; the housings had built-up areas around the bolts so the bolt length was the same as the 36mm pump.
Imageshack,... I know it's here somewhere in these 18 pages,...
Ahhhh ha:

One pump is 30mm and one is 36mm.

Greenmachine · Post by **Greenmachine** » Thu May 01, 2008 11:30 am

I think I was looking at a 27 vs. 30 and the 30 didn't have the spoiler but it did have longer bolts.

Anyway, thanks for the help all, it was pretty clear when I pulled out the gears on those pumps. Not much mystery to those.

I went with the late model crankshaft after reading old posts where the key gets plowed by the sprocket on the old ones.

The comment to expect an argument from the shop on the bore tolerances was dead on.

shop guy: "I been doin' this for 26 years and that is waaay to tight for a diesel"
me: "but these are the official specs"
sg: "Well we'll see about that when we check the real official specs"
goes to computer looks up motor
sg: "Well I'll be damned!"

he did a good job in the end.

2 weekends later and I have a 'new' motor. Really runs well, but haven't got it out of the barn yet to see if/how she drives, but she gave up smoking. I'm pretty excited about having a new clutch too.

surfcam · Post by **surfcam** » Thu May 01, 2008 1:58 pm

Way to go Greenmachine. Your enlighting to the world in the way of the diesel. You have also helped the next guy that comes along for a rebuild. He will get a long running quite diesel as well.

Post by **Fatmobile** » Thu May 01, 2008 9:38 pm

I went with the late model crankshaft after reading old posts where the key gets plowed by the sprocket on the old ones.

It's the later cranks with the small key that have the problem.
I've never heard of an early crank key shearing.

Greenmachine · Post by **Greenmachine** » Mon May 05, 2008 5:42 pm

Clarification: I meant I went with no key, the pulley is notched to match the notch on the shaft.

Post by **Fatmobile** » Tue May 06, 2008 1:29 am

I went with the late model crankshaft after reading old posts where the key gets plowed by the sprocket on the old ones.

Clarification: I meant I went with no key, the pulley is notched to match the notch on the shaft.

Right, you used the crank that has the keyway problems.
If the bolt gets a little loose there is nothing holding the sprocket to the crank. If the sprocket even moves a 1/16th" away from the crank it will quickly wear away and let loose.

With the older/longer key, you would probably hear stuff rubbing on the timing belt cover before anything bad happened.
I think you picked the wrong crank, for the wrong reason.

Kneale Brownson · Post by **Kneale Brownson** » Tue May 06, 2008 1:01 pm

I thought the keyway problem was attributed to the bolt, and the newer bolts were supposed to clear up the problem????

Post by **Fatmobile** » Tue May 06, 2008 7:21 pm

I'm not sure if any have failed with the newer style crank and new bolt,.. but I think a few have.
That's why they machine the end of the crank to fit the D sprocket.
No key, or little notch,... it's D shaped and the crank has a flat spot to match it.
Started doing it on the '98 TDI I think.
Good info on the GTD forum.