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Rut

Rut

Obi Wan
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I finally installed the new manifold studs, washers, and nuts, carb and header. I also installed or should I say, placed the Harley muffler on the exhaust pipe without clamps since I need my main pipe bent to fully fit. This gave me a chance to run the engine for about 20 to 30 minutes without neighbor complaints. I brought the engine up to temp and it idles pretty well once warm, but bogs when you give it gas and smokes a lot. This may be due to the PCV installation since I could be drawing a little oil from the separator. I'll pinch off the hose and see what effect that has on the smoke and leak. Without the muffler I couldn't run it too long because it was soooo loud. When warm I'm running 40 to 45 psi at idle (1000 rpm) and the temp reaches 165 on both temp gauges, 1 in the head, 1 in the rad. The 1275 engine was 'rebuilt' according to the po and it includes a Kent street cam, Weber, and headers with a few other modifications. I say 'rebuilt' because of the use of old hardware on the outside. My thoughts are that it's running rich, but I have no experience with a Weber set-up and it's been almost 40 years since I've really fooled with an LBC. Anyone running a similar set-up have any thoughts? Thanks, Rut
 
what weber do you have and has it been on the car or did you just add it ?
is the smoke black ? or blue white ? or just white?
if black it rich, if blue white it oil, if it white it,s water
when dose it smoke at idle? when you rev it ? or after you rev it and went back to idle ?
 
what color are the plugs?
 
Thanks for the replies...it's a downdraft Weber with a Pierce manifold and the smoke is gray, but smells of oil. The engine has about 1 hour on it since a rebuild several years ago and is not broken in. I'll guess that the plugs will be oily since the engine ingested quite a bit of oil during my PCV experiment. The engine smokes at all rpm ranges and I would say that it's the same amount based on rpms. The engine did not seem to smoke as much before I put the muffler on it, but I guess that's because I was unable to run it very much. As I recall the amount of smoke prior to my PCV installation was just about 0. My WAG is too rich or PCV...
Thanks, Rut
 
unhook you PVC let it run and see of it gose away
 
Hooey, that's my next step...just need a large bucket to start catching the oil!
 
Hate to be the barer of bad news but I don't think spridget owners have had much luck with the weber downdraft dgv carb set up. I had a car that had it on it and it came with a coffee can full of weber parts the PO had been swapping to get it to run right. He got it to not bog and give plenty of power but it only got 19 mpg and smoked black. I sold the car since my only intention with it was to turn a buck. Some of the trouble can probably be blamed on the carb which seems to work on lots of other stuff.
I'm sure others have opinion's on this so hopefully you will get more feedback.

Kurt.
 
I know that there has been a lot of talk about PVC here
but this is the way i would set it up
 

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Kurt, thanks for your insight. I have a 948 that came with the car and it has the original carbs, but the po sold the carbs that came with the 1275. I may be looking around for a set in the near future if I can't track down the problem and I isolate it to a 'carb' problem. My goal is to have a running car for the summer and fall and restore it next winter. I'm not too concerned if I have to change them out, but I wish I had the originals. Don't get me wrong, I don't want to spend money I don't need to, but my ultimate goal is a restored bugeye with a 1275. This is all subject to change as most projects are.
Thanks, Rut
 
If the 948 has the SU HS2 carbs, thats a good start. The intake manifold will not have the port for the PCV, but you can get a later manifold cheap. You could use the 948 manifold if you install a port for the PCV. You might need to rebuild the carbs and change the jets. There's another thread on here about this subject "carbs" that has some info.
 
Steve, thanks for the additional info. I've not checked what carbs came with the 948 since it's in parts with a spun main bearing in a couple of boxes. It's a 1960/61 bugeye and it may have later carbs. I think I have a couple of extra manifolds as well.
Thanks, Rut
 
Hooey, thanks for the schematic...pretty much the way I've got it, but without the extra baffled container. The carbs I have are AUC 1341 & 1342 with tags that both read AUD 136R. I also have 2 intake manifolds and a heat shield. Any idea if these are HS1 or HS2?
Thanks again, Rut
 
AUD 136 are HS2s and were used on both 1098 and 1275s. Should work. Make sure you have a front and a rear since both tags are "R" for rear. The tags often get changed or lost.
 
Steve, the numbers cast into the body of the carbs are AUC 1341 and 1342 and I believe they are a matched pair. They come complete with all linkage and plumbing, spacers, etc. I'll clean them up in case I need them.
Thanks, Rut
 
I disconnected the PCV and a lot of the smoke went away. The smoke that's left is more blue than gray and it's pretty much gone at idle, with light puffs when I rev the engine. The oil leak returned with a vengeance so it seems like I need to balance the flow thru the PCV to fix both problems.
Thanks again, Rut
 
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