Since it was 40 degrees out yesterday I started up the old 37 coupe & let it warm up. However, I still have a problem. When I try to rev the engine it stumbles. When I raise the rpm to 1500-2000 it boggs down. Even at higher RPM it will boggs down. An old mechanic friend thought I might need the air cleaner on the carb as it possibly could be getting too much air. If I try the air cleaner & it still stumbles & boggs down, what might be the possible causes or best place to start investing? My initial thought is the carb but could it also be sticky valves? The coupe has the original 212 ci engine in it from Hudson. Both the carb & fuel pump were rebuilt by my mechanic friend a little over a year ago. All fuel lines are new and the tank was cleaned out about a year ago with this being the 1st time gas has been back in the tank & new system. Sent from my iPhone using H.A.M.B.
What is the choke doing? If the choke is mostly closed, it will do things like that. There are a lot of other possible causes, but this kind of thing is hard to diagnose over the internet. If you can take a video, and post it to youtube, with a link here, we might be able to get a better idea of what's happening.
Ben Sitting? (an old Indian friend) Sounds like something is plugged in the jetting. Take the carb apart and clean it out.
Changed the condenser didn’t change anything. Dang I was really hoping. Sent from my iPhone using H.A.M.B.
I’m wondering if the valve clearance is off but I’m just grasping at straws. Sent from my iPhone using H.A.M.B.
Hook up a vacuum gauge and see what it’s doing. And as squirrel stated look at your choke. Timing will do that as well Was the engine running fine before?
If it idles well but doesn't want to rev it could be a fuel delivery issue, dirty fuel filter, plugged up fuel tank vent etc....as has been stated make sure the choke is opening, if it is opening and the engine increases RPM when attempting to rev it a light bit and pull the choke out a little bit at a time this verifies either fuel mixture issues ( plugged jets etc.) or fuel delivery issues...also if the vacuum drops ( on a gauge) and stays low as the engine is " bogging " it could be a blockage in the exhaust ( rat nest in the muffler, collapsed baffle etc.)
As a few here have said, tough to diagnose with the limited info. I usually start at fuel delivery, then check vacuum leaks (if they choke is staying closed and it’s idling ok you may have a vacuum leak somewhere). Then I move to ignition and timing (how are the points? Gapped properly with accurate dwell?). My truck was having an off idle stumble that got worse as it warmed, it was ignition related. Sent from my iPhone using The H.A.M.B. mobile app
The coupe sat for over 15 years before I started working on it. I got it going around 2 years ago. Once running again I had one stuck lifter. However even after that was freed up, she’s never ran right. Previously I had a huge intake leak and she wouldn’t even idle once warmed up. Turned out to be a ball valve under the intake was missing the ball & sucking air. I also replaced gaskets and went thru the cooling system. Before starting her up I also gave her a tune up, rebuild the carb & fuel pump. Gas tank cleaned out so I know it’s good & no pickup tube blockage. New gas lines and new fuel filter too. Timing was set but I may need to advance it a bit to see what it does. There could be a blockage in exhaust as she spent a couple years in my barn at the last house. I’ll have to remove the exhaust pipe before the muffler & see what that does. Hope that info help & thanks for great ideas, I’ll keep at it. Sent from my iPhone using H.A.M.B.
the thing about posting video...there are lots of guys here with years of experience troubleshooting engine problems. But there are so many clues they can get from seeing/hearing it run, that they can't get from you using a few words to describe it. If possible, shoot some video, it will probably save you time and money to do so.
Not sure how this will work but hopefully this video will work of the engine running. I have the exhaust disconnected at the manifold in the video. I wanted to see if I may have had a plugged muffler but it still ran the same, no improvement. Sent from my iPhone using H.A.M.B.
Just in case someone was wondering what was causing the problems with my splasher 6 cylinder engine? Here’s the reason: Sent from my iPhone using H.A.M.B.
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