I was hoping you guys could help me figure out what is wrong with my weber carbed 2.0 engine. I bought a rusted out parts car and installed the engine into my 71 when my 1.7 crapped out. The engine starts right up (except when hot, but it is a 914, what do you expect) but when it is idling it smokes like an overdone bbq grill. Once the rpms rise above about 1800rpms or so the smoking goes away and the engine seems to run fine. The only other time the engine smokes is when I have been at speed and suddenly engine brake (as in when slowing down coming to a speed zone, etc). When I put my hand over the exhaust pipe at idle I notice that the engine is both blowing exhaust and sucking a little bit. I have a crankcase breather tube but do not have a PCV valve on the breather. I think that is all the relevant info, if you guys want any more details I can provide them. Any ideas you guys have on what could be the problem would be appreciated!

smokes out of tailpipe or off the sides?


if it smokes at idle and decel...worn valve guides is the diagnosis....

b

Hey
Welcome to the club

Sorry man sounds like you will have to open it
I think Britt might be rite on this one

Dual carbs don't have a PCV, just a breather box. If you suspect a crankcase overpreasure, unscrew the oil cap and see if it helps (don't loose it on the road, it makes a FKing mess).

Later

actually man, some people actually drill through the PCV valve to lessen the crankcase pressure....oh and are your heads tapped for the little breather fittings? that helps too.

b

QUOTE (Jon Runaas @ Nov 2 2005, 07:51 PM)

I notice that the engine is both blowing exhaust and sucking a little bit

when was the last time you adjusted the valves ???

Andy

I bought a seal kit for the 2.0 and the valve guides weren't in it. Were do I get them?

You get them through your friendly neighborhood machinist, who also installs them and reams them to size for you.

BTW, you didn't mention what color the smoke is. Black is usually partly-burned fuel, and means you're running too rich. White is usually water, so it shouldn't be a factor in our cars. Blue is usually oil. Blue smoke on overrun (coasting at high RPMs in gear) usually means the exhaust valve guides are worn. Smoking under load usually means the rings are worn. Try a compression test and then a leak-down test to see what kind of shape your rings and valves are in.

--DD

Sounds like the I'm looking at worn valve guides...I suspected that but wasn't entirely sure. Any more thoughts about the slight sucking on the tailpipe? I halfway adjusted the valves (I was in an extreme hurry and just made sure I had some play in all the rockers with pistons at TDC) when I installed the engine. Would you suggest (now that I have more time) re-checking all the valves? If they all are adjusted right and I still have some suction at the tailpipe, what could be the cause? Thanks for all the help guys, I really appreciate it!

If you suspect sucking at the tailpipe, the exhaust valve is still open on the intake stroke...meaning bent valve / burned valve / to tight a valve / exhaust valve not seating (broken / weak spring)...but, it should missfire and possibly backfire thru the intake.

OR

a non-stock high overlap cam.....



Well, it's at least what I think anyway