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Bf 25 running issues

I had originally got a hold of someone named jgmo but I can’t get in contact with him, he was really helpful.
Anyways the problem he helped me fix was the passage way under the bowl of the top carb was plugged up with mud. I cleaned it out and it runs perfectly but it smokes( not oil smoke too much fuel smoke) so it’s running pretty rich. My conclusion was the bystarter wasn’t shutting off so I tested it and it was not working so I ordered a new one. It cold started just fine ( that was my problem last time) but after the cold start it wasn’t running properly it was still smoking a little bit and wouldn’t idle at all. The bucket of water I had it running in started to appear cloudy. It was also backfiring . Anybody got any ideas?
 
Hi Cade,
Sorry you're still having problems.

A little more info please...

So the NEW BYSTARTER didn't have any effect? Or, you haven't tried it yet?

The smoke is BLACK?

When you say it's backfiring, do you mean from the exhaust or the intake?
 
Ok, just read your PM...sorry I missed it previously.

Does the water in your bucket stay cloudy or does it clear up after you shut it off?

If it clears up after a bit, I'd be worried that the engine is overheating.

If it stays cloudy then it could be a fuel leak. I don't know.

Hopefully, your waterpump is in good shape and that "bucket" you're using is big enough. Even if it's a big trashcan, you can't run very long without adding cool water since the exhaust is rapidly heating it up.

At any rate, check your oil and make sure no gas is mixed in with it. If in doubt, change it AND the filter to prevent engine bearing damage while testing.
 
No the new bystarter made it run like crap ( I assume because it’s working and it shuts off)
However it still smokes white smoke a little bit I know it’s not oil because I can see gas in the bucket of water I’m running it in. It seems like it needs that little extra fuel to run properly. It’s backfiring out of the intake it appears
 
No the new bystarter made it run like crap ( I assume because it’s working and it shuts off)
However it still smokes white smoke a little bit I know it’s not oil because I can see gas in the bucket of water I’m running it in. It seems like it needs that little extra fuel to run properly. It’s backfiring out of the intake it appears
Don’t pay attention that I just now see you say my message
 
Ok, just read your PM...sorry I missed it previously.

Does the water in your bucket stay cloudy or does it clear up after you shut it off?

If it clears up after a bit, I'd be worried that the engine is overheating.

If it stays cloudy then it could be a fuel leak. I don't know.

Hopefully, your waterpump is in good shape and that "bucket" you're using is big enough. Even if it's a big trashcan, you can't run very long without adding cool water since the exhaust is rapidly heating it up.

At any rate, check your oil and make sure no gas is mixed in with it. If in doubt, change it AND the filter to prevent engine bearing damage while testing.
It clears up but it stays cloudy a little bit. It’s not peeing very well I have a new water pump for it but I wanted to fix the running issue before I do that. When I switch the bystarters back a fourth ( the broken one and the new one) they run completely different. With the new one it cold starts just fine and then it will shut off after it gets warm.
 
It clears up but it stays cloudy a little bit. It’s not peeing very well I have a new water pump for it but I wanted to fix the running issue before I do that. When I switch the bystarters back a fourth ( the broken one and the new one) they run completely different. With the new one it cold starts just fine and then it will shut off after it gets warm.
Not like overheating warm just like 25 seconds
 
Well, I think that you had better replace the pump before running it anymore but....your decision.

That new bystarter sounds like it's doing EXACTLY what it's supposed to do.

Only you know the history of this thing. I don't think we ever discussed it before.

Backfiring from the intake usually indicates that it's running LEAN so your question about the little orings might be pretty important.

But, backfiring can also be caused by a vacuum leak, tight valves, a burned or damaged valve or the timing being off.

All things to check and eliminate when dealing with something like this.

I don't have the shop manual for this engine so I can't walk you through a timing check or valve clearance check/adjustment.

The GOOD news is that it starts "crisply" and easily so I wouldn't suspect a damaged valve.

The BAD news is I can't be entirely sure why it's doing what it's doing so all I can suggest is to change oil and filter, make those checks ((timing, valve adjustment) and replace the waterpump BEFORE running it anymore.

The BADDER news is that with it backfiring like that, you COULD damage an intake valve. If that happens, then your engine would truly be in trouble.

If the pump is badly worn, I HIGHLY recommend a complete repair kit, not just a new impeller.

If timing and valve adjustment is good and the symptoms don't improve, then it's very likely there's more carb work needed which would certainly involve replacing those three tiny orings along with some other things I brought up in your first post.

I know this ain't makin' you happy but it's pretty much all I've got to offer.
 
Well, I think that you had better replace the pump before running it anymore but....your decision.

That new bystarter sounds like it's doing EXACTLY what it's supposed to do.

Only you know the history of this thing. I don't think we ever discussed it before.

Backfiring from the intake usually indicates that it's running LEAN so your question about the little orings might be pretty important.

But, backfiring can also be caused by a vacuum leak, tight valves, a burned or damaged valve or the timing being off.

All things to check and eliminate when dealing with something like this.

I don't have the shop manual for this engine so I can't walk you through a timing check or valve clearance check/adjustment.

The GOOD news is that it starts "crisply" and easily so I wouldn't suspect a damaged valve.

The BAD news is I can't be entirely sure why it's doing what it's doing so all I can suggest is to change oil and filter, make those checks ((timing, valve adjustment) and replace the waterpump BEFORE running it anymore.

The BADDER news is that with it backfiring like that, you COULD damage an intake valve. If that happens, then your engine would truly be in trouble.

If the pump is badly worn, I HIGHLY recommend a complete repair kit, not just a new impeller.

If timing and valve adjustment is good and the symptoms don't improve, then it's very likely there's more carb work needed which would certainly involve replacing those three tiny orings along with some other things I brought up in your first post.

I know this ain't makin' you happy but it's pretty much all I've got to offer.
Thanks so much man I’ll take your advice and see what happens I wouldn’t think it would be anything to do with the valves just because it runs very well with the broken by starter in which means that it’s being starved of fuel when that passage way is closed off
 
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