Pum coil issues

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no, just run it first: I think you are over complicating things. Unless you cool the engine with liquid nitrogen it will not stall.
But elaborate a bit on what you have set your needles at, what carb you use and may be some pictures. You're making this a complicated puzzle, that I think just originated from the butterfly at the carb being closed completely and no coil or other needle issue. . If you have a WT257 carby: L needle 2,25 turns out ( from closed) and H needle 1,25 turn out, your butterfly not complete closed, it should run.. And yes it's a boat so tune it under load on the water, not on land with no load.
 
no, just run it first: I think you are over complicating things. Unless you cool the engine with liquid nitrogen it will not stall.
But elaborate a bit on what you have set your needles at, what carb you use and may be some pictures. You're making this a complicated puzzle, that I think just originated from the butterfly at the carb being closed completely and no coil or other needle issue. . If you have a WT257 carby: L needle 2,25 turns out ( from closed) and H needle 1,25 turn out, your butterfly not complete closed, it should run.. And yes it's a boat so tune it under load on the water, not on land with no load.
I think Ryan mentioned before,on previous page,he had the idle stop screw wound all the way in,to keep it running,,which I thought was maybe too rich on the low speed mixture screw,,I'm assuming all walbros have a low and high mixture adjustment
 
Ok so first how can I tune a carb with the boat in the water when if its on land it won't hold an idle for any period longer than 1 minute? The boat has a clutch so it should be able to hold an idle. The point I'm making with this carb is the fact that It's one or the other, if I want it to idle I have poor transition from low to high if I blip it out of the water as it bogs and will die if I hold it. If I tune it to get the transition better I have to richen the low like an 8th turn or a little more to have it run better but then I lose the ability to idle as once I comes back toward an idle it will just die if I let go of the throttle all together... my day job is a diesel mechanic so I have an idea what I'm doing I'm not over complicating it what so ever I guess I'm just not saying it right for you to understand what my issue is @rhomodel . The engine is showing behaviors that are unique to itself where my other boats don't act this way, the needs are set to what the stock adjustment would be for the 1048 and turned a little bit from there and I couldn't tell you exactly where their at because to me it's pointless to keep track because I can't get it to just behave even at stock settings....

I've tried 3 carbs and I've changed all of the gaskets,seals,piston ring on this engine and the engine runs better but still has this issue and it smokes like hell when it's running even if I lean the carb out so that's why I'm perplexed
 
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Ok so first how can I tune a carb with the boat in the water when if its on land it won't hold an idle for any period longer than 1 minute? The boat has a clutch so it should be able to hold an idle. The point I'm making with this carb is the fact that It's one or the other, if I want it to idle I have poor transition from low to high if I blip it out of the water as it bogs and will die if I hold it. If I tune it to get the transition better I have to richen the low like an 8th turn or a little more to have it run better but then I lose the ability to idle as once I comes back toward an idle it will just die if I let go of the throttle all together... my day job is a diesel mechanic so I have an idea what I'm doing I'm not over complicating it what so ever I guess I'm just not saying it right for you to understand what my issue is @rhomodel . The engine is showing behaviors that are unique to itself where my other boats don't act this way, the needs are set to what the stock adjustment would be for the 1048 and turned a little bit from there and I couldn't tell you exactly where their at because to me it's pointless to keep track because I can't get it to just behave even at stock settings....

I've tried 3 carbs and I've changed all of the gaskets,seals,piston ring on this engine and the engine runs better but still has this issue and it smokes like hell when it's running even if I lean the carb out so that's why I'm perplexed
I can understand the frustration,and you/ve changed seals,gaskets even carbys etc,,did you check the cylinder base surface on the case for straightness/vacuum leak?,,What about if you set the low needle to get good idle,and richen the high end needle a bit, for the transition
 
My next step was to pressurize the engine to check for leaks and if I adjust the carb to have a good idle then I have poor transition and it will then bog off idle. There's no middle road for the carb to atleast work decent without manually adjusting idle from the radio
 
Was told 8 to 10 oz a gallon.. think I'm somewhere in the 18 to 20:1 ratio. I was told more oil content for these marine engines
 
I can understand the frustration,and you/ve changed seals,gaskets even carbys etc,,did you check the cylinder base surface on the case for straightness/vacuum leak?,,What about if you set the low needle to get good idle,and richen the high end needle a bit, for the transition
Rod,
70% to 80 % of the throttle range is controlled by the low speed needle. If he adjusts the low speed needle to idle with the butterfly slightly cracked and have it transition to high rpms on the bench, don’t hold it there just see if it will transition with no stumble. Then richen it 1/8 turn and try it in the water.
 
Yea can't get it to transition without completely losing the ability to idle and I can only richen it and if I go a hair leaner it will die and bog terribly
 
Rod,
70% to 80 % of the throttle range is controlled by the low speed needle. If he adjusts the low speed needle to idle with the butterfly slightly cracked and have it transition to high rpms on the bench, don’t hold it there just see if it will transition with no stumble. Then richen it 1/8 turn and try it in the water.
Cheers John,,I assumed the low needle affected a smaller range,,This poor guy has tried almost everything with different carbys and engine reseal job to get this thing running well..,,I'm running out of ideas lol,,
 
The engine should idle and you should be able to screw in the low speed until idle starts to increase as mix goes lean then come back out until it starts to four stroke then back in to a clean idle. I always like to visit both ends of the mix with a low needle on a new setup if the recommended needle setting is unknown. Then once you have a good idle mix gas it and see it it falls flat or takes throttle well and adjust high until transition is good but on rich end of that mix and test on the water after that with a load and at running temperatures.

There is a problem if the carb doesn't run the engine at idle and get reaction from low needle as described above. If you have to give it a ton of idle air with the butterfly open excessively just to get it to run then definitely not right somewhere.

Is it using a stock plastic intake or aftermarket one ? Vacuum signal getting to the carb ? Diaphragms all good ?

Try one more different known good carb possibly if you can.
 
I'll label my trouble shooting
1. Rebuilt both 1048 and 257 carbs with all new internals and pop pressure checked.
2. Changed coils.
3. Went in both directions with needles.
4.re sealed the entire engine.
5. Using a known good plastic isolator.
6.new piston ring and checked scoring. Engine has only 2 hours on it but it's a 2nd hand engine
7.good clean fuel
8. Boat has a water pump and I just rebuilt the pump with a new walbro rebuild kit.

So my latest observation is when I run the engine for a few minutes I pull the plug and its soaked...I was told try one heat range hotter maybe it will help

I wonder if it was an air leak I would need more fuel to get the engine to behave better but it's acting like it wants more air
 
plug off the crankcase line to the water pump and try it ?

Have you tried the carbs on another motor and see if problem follows the carbs?

disconnect any shutdown wires from the coil.
test again... rule out any issue there.

did you pull the flywheel with magnets???
shaft and keyways look good ?

just throwing out ideas...
 
Did previous owner cut on the motor and change port timings? Piston skirt cut on ?

I've seen motors that the piston freeports on the exhaust because the piston skirt has been cut or port timing too high. They will run good at high RPM, but won't idle worth ****.
Which is ok if you know about it and keep the motor revved up....if someone built it for all out racing in a hydro, it may not idle like you are wanting to....

just another thought...
 
Yes I pinched off the line to the pump
The engine is a gizmo 30 plus
The issue is just following the engine and not the carbs.
No kill switch attached while running
I disassembled the entire engine and rebuilt it and everything looks good
I too am starting to believe this gzr engine got a little wild with the porting as I see it looks hand ported and this is most likely causing the poor idle characteristics.

This just reinforced why I like to build my own engines and use new parts
 
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Not sure if you did an engine pressure test ,but if not you should even after a fresh rebuild
If there is any air leak it will show up right away
Jack
 
Alright it's fixed. Thank you so much to everyone that posted! It was the insulator 🤦‍♂️ I checked it again on a flat surface and yup it was warped to the point a gasket would not seal...thanks again everybody im glad I joined this forum you guys are a great community 👍.... @Steve Stafiej no it doesn't have those seals
 
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Thanks! @Wasted wages this engine went to a friend but I cannot sell anything to anyone if it's not to my standards. The engine helped fun a tig welder so I have more freedom to be able to modify some parts as needed. The next video is of the seaducer!! Should be up by Sunday just waiting for parts
 
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