88Hp will not start/run unless..

[bwhite41]

I have what we think is about a 1990 88Hp SPL. The plate for the serial number is gone. If I open the red switch and bypass the carbs I can run it for a short time. If I lock that switch where it should be it just dies. We rebuilt the carbs, changed all the fuel line from the tank to the carbs, and rebuilt the fuel pump. Gas just doesn't want to flow. If I disconnect the hoses I have free flow. I have spark in all 4 plugs and equal compression in all cylinders. I'm at a loss and about to swallow the shop fees. Ideas?

 

[fireman57]

Leave that switch where it is supposed to be and make sure that whey you put the air silencer and carb linkage back on you don't accidently have the choke on too. Don't ask me how I know. I will admit nothing. Also, did you remove and do a thorough carb cleaning. You might have floats that are stuck.

 

[bwhite41]

Yes we did, ran tiny wire through all the carb holes, sprayed them out, blew them out. The old floats were bent a bit, the new ones we left straight and flat. Did the flip upside down test and the were all laying as the shop told me. Do I bend the float tabs?

 

[emdsapmgr]

Not sure what you mean when you say in this statement: "If I disconnect the hoses I have free flow." Could you elaborate? Do you mean the fuel primer hoses? Is the fuel hose oriented in the correct direction for fuel flow? Any change if you constantly prime the fuel hose bulb?

 

[bwhite41]

I'm just saying none of the fuel lines are blocked. Arrow on primer pointing correct direction. Even with priming it just seems carbs are starved

 

[pn]

If your spray a fuel mix down the carbs and it fires then you have a fuel problem....if not then i'm guessing timing...that red switch with a schrader valve is an electric cold start primer. one way on, one way on to bypass fuel tank for fogging. r u getting fuel? check this by dissconnecting the fuel line right after the cold start and either crank you engine or pump your primer bulb either electric or manual. caution: fuel should spurt out. if it doesn't turn the lever and try again, if it doesn't squirt then you have a restriction upstream. possibly everything is good except timeing, or vent for tank.

 

[pn]

If your spray a fuel mix down the carbs and it fires then you have a fuel problem....if not then i'm guessing timing...that red switch with a schrader valve is an electric cold start primer. one way on, one way on to bypass fuel tank for fogging. r u getting fuel? check this by dissconnecting the fuel line right after the cold start and either crank you engine or pump your primer bulb either electric or manual. caution: fuel should spurt out. if it doesn't turn the lever and try again, if it doesn't squirt then you have a restriction upstream. possibly everything is good except timeing, or vent for tank.

 

[emdsapmgr]

Try a test. Do a normal cold start with the choke (key pushed in.) (fast idle lever raised somewhat) Crank the engine for 15-20 seconds. Pull the spark plugs. Are they wet or dry?

 

[bwhite41]

Dry

 

[pn]

floats upside down?

 

[bwhite41]

No but, we tore it down and started squeezing on primer bulb. Gas started to pour out of one carb and not the other. Which one is wrong?

 

[bwhite41]

No but, we tore it down and started squeezing on primer bulb. Gas started to pour out of one carb and not the other. Which one is wrong?

 

[bwhite41]

How can I tell if floats are upside down?

 

[fireman57]

there is a groove on one side of the float, if you look you will see that it fits over the hump on the carb body. common mistake.

 

[emdsapmgr]

So the engine is not getting any fuel. Just where is the fuel coming out of the one carb?

 

[bwhite41]

Ok. Figured it out. Carbs are good now. Any advice on adjusting the timing?

 

[fireman57]

You should not have to adjust it. do a link n sync on the carbs.

 

[emdsapmgr]

Agree with fireman.

 

[bwhite41]

What's a link n sync? I'm getting a slight mishit/backfire every 3-4 seconds

 

[bwhite41]

Maybe I should spell out miss hit so I don't get censored