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Fri Apr 02, 2004 8:18 am

I just finished building a stock motor for my fuel injected '71 squareback and now I'm pretty uncomfortable with what I see. For just a little history, the car has run, mostly at a high idle for about an hour while I figured out why it was pouring out black smoke and fouling plugs. It ended up being a problem with the manifold pressure sensor that I chased down and repaired. After fixing the problem and replacing the plugs again I started it up again and it seemed to be running great with no smoke. Last night I decided to drive it for the first time down the street but then I started to get quite a bit of blue smoke out of the tail pipe. I only drove it about a mile and half but the motor felt great. I has very good power and is extremely smooth so I'm confident my fuel injection problem is fixed. I pulled the plugs last night to see if I could find any plugs that looked like it was cover with oil. The plugs looked good and didn't smell like oil so I did a compression test as well. The low cylinder was 125lbs and the high cylinder was 135lbs. I have changed the oil three times in the hour of running with 10w30 but should I be running anything thicker during break in? I know Synthetic oil will not smoke but I don't want to mask the problem and I've always been told to break in a new motor with conventional oils. I could even see the smoke behind the car as I was driving it, is it normal to get this much smoke on a new motor? I'm sure I spaced the ring gaps about 120 degrees apart when I put it together. I also checked the vent hose from the case to the air cleaner to make sure it wasn't blocked and building too much pressure inside the case. I'm terribly worried about this and I'd rather not tear down the motor again if I don't have to, type 3's are more of a pain. I haven't built a motor in over ten years so I can't remember what to expect. Maybe I need need a thicker oil and let the rings seat? Any help is greatly appreciated.

Thanks,
Vache

Fri Apr 02, 2004 8:40 am

well,I just started my 1835 last night for the 1st time in 2 yr.s since it was built and the only smoke I had was a little black from my fuel mix which I got straight in about 2 minutes besides that it didn't puff at all so I'm not sure what to say,I'm not an expert motor builder cause I have people to help me along and teaching me,I'm more of a paint guy myself.

Fri Apr 02, 2004 8:59 am

That's my problem, I'm a paint and body guy as well. I don't care much for motors...

Fri Apr 02, 2004 11:58 am

I like 'em. They're nice and helpful and useful... :D
But they're a pain to work on. :x

Fri Apr 02, 2004 1:45 pm

did you leave the oil ring gap at the bottom of any of your pistons?
it lets oil travel up the cylinder and into teh combustion chamber when you let it sit, (like overnight). BIt should only give you a puff of smoke when you first start up. was there a big variation between compression between two cylinders.

Fri Apr 02, 2004 2:10 pm

if you ran the car pouring oil into the combustion chambers it probably got in the pipes too. This oil will take a while to burn out. Try taking off the pipes and see whats in there.

Fri Apr 02, 2004 3:15 pm

I didn't intentionally leave a ring gap at the bottom. I tried to space them at 12 o'clock, 5 o'clock and 7 o'clock. I think I'm going to change the oil again and run it for a while and see if it statrs to deminish.