Hi all,

I have a 72 250 M130 W zeniths. Runs great cold and even pretty warm but after I get off the highway and hit a stop light, if I just let go of the pedal for a few seconds and then accelerate, let it roll, I'm ok.

If I touch the accelerator right off it want or does stall.

Any advice?

Thanks

G

Check to see if the squirt of gasoline occurs in both carbs. This can be done with the engine cold.
Aternately, most off-idle conditions can occur from a lean condition, caused by a loss of vacuum. When were the carbs rebuilt last? The base gaskets easily deteriote with age.

__________________
1970 280S M130 engine- good runner
1971 250 M130 engine- #2 rod bearing, gone
1971 280SE (blown engine,parts car)
1977 German 280S W116-only 33 years old

Thanks Munich,

I'm getting a nice squirt out of the pumps.

The carbs where rebuilt last summer. I sprayed carb cleaner around the base and don't see a change in RPMs

I take that back.

I just redid the leak check with brake cleaner this time and it looks like the last 2 manifolds are sucking air.

How hard is it to replace the manifold gasket on this beast?

Thanks

G

Pulling the manifolds on the m130 is not bad. The worst nuts are usually the ones that connect lead muffler pipe. Good opportunity to check position of the butterfly valve that preheats Zeniths too. It should be mostly closed never wide open, as i'm sure you know.

And at first reading your initial post it occurred to me the distributor centrifugal advance might be sticking when coming off the highway, saw this alot with m180's.

"Good opportunity to check position of the butterfly valve that preheats Zeniths too. It should be mostly closed never wide open, as i'm sure you know."

Not really, are you refering to the butterfly in the exhaust? I know they are in there but no way of checking if they are operating properly.

Also, I have been tearing appart my manuals and CD to find the torque settings for the manifold and any other bolts I may find on the way.

I have a bad habbit of not tightening enough or snapping bolts. The torque wrench is my friend. the torque wrench is my friend, the tor...

Any point in retightening the bolts in case they are loose? I had a shop replace the head a few years ago, not sure if they removed the manifold and didn't torque it correctly.

Thanks

I seem to remember torque settings for manifold nuts being soft, somewhere around 28-32, maybe 36 tops. But yeah, you might find success smacking em with rubber hammer and tightening em up. And if you're pulling the mannies and takin em to the bench, why not seperate em and take a look at the butterflies? They are rarely operative but can warp yer Zeniths if frozen wide open.

Sounds great.

Is there a way to tell if the butterflys are working from the outside? are there butterflys on both manies?

I had the same issue in 2004. The problem with turning them with vise grips is the butterfly shafts can be so corroded that a fracture occurs. I ended up taking off the manifolds, soaking the rusty shafts with "P B blaster" and turning the butterfly valves so the carbs won't over heat. The climate where I live isn't too cold, so I never noticed any warm-up issues.

__________________
1970 280S M130 engine- good runner
1971 250 M130 engine- #2 rod bearing, gone
1971 280SE (blown engine,parts car)
1977 German 280S W116-only 33 years old