No spark 3&4 87 125

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Stokes760

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I have a few questions for befor i fire this up.
1. It's been siting for no idea how long. Should i run a bit of fuel .25 gal with a rich oil mix maybe 40:1
my thoughts is get everything lubed up and if carbs run lean I have a safty zone with extra oil.
2. With no temp gauge and no buzzer whats safe head temp with ir temp gun?
3. To kill motor ground the white leads off cdi pack?
 
jerryjerry05

jerryjerry05

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You could run extra oil? Probably not needed.
I believe the thermo is a 130d.
Most times if the heads so hot you can't leave your fingers on it, then it's too hot.

I just hit the choke bar to kill it.
 
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Stokes760

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So replaced the bad cdi pack and got spark on all 4. Added fuel got to back fire not a bad one but still not right. Tryed starting fluid to see if i could get to run same issue. Any ideas where to start
 
jerryjerry05

jerryjerry05

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Usually the timing doesn't move unless you move it.
Even turning the trunion a turns or two in either directions wouldn't cause that much of a problem.

If you have spark on all 4 then the problem is fuel related.
You do anything to the carbs?

Make sure the air screws are set and there is no water in the fuel??
I have a second tank just to test motors.

An inline water/fuel separating filter can solve some problems.
A boat that sets for a long time can get a bunch of water in the tank.
 
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Stokes760

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Jerry i was running of a sepaate gas tank new line and primer bulb. Is there a 3/8 barb for the fuel pump I bought 3/8 line. I didn' touch the carbs hopeing they were set well befor. Ill check the idle curcut 1.25 turns out? U was thinking fuel problem thats why i tryed starting fluid. After cranking choked when i dechoke fuel dribbles out of bolth carbs. I was going to rebuild the carbs anyways I just want it to run befor i spend more money and time. Any good carb kits just need gaskets or a full kit. Ill do the link and sink it seems easy and one more thing to check off the list for trouble shooting. I need to find a good wireing diagram so i know spark timeing is correct and then spark advance
 
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Stokes760

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Found a good wireing diagram that showed I had coil packs backwards and looking at the bussbar makes alot more sence now. I as able to get to fife up but not stay running had to play with throttle position and choke setting to get to run for an extended time. I' going to check timeing and sink carbs tomarrow. I want to rebuild carbs do i need a full kit or are most pieces still good and I only need gaskets. Want to rebuild fuel pump is there a fuel line inlet cap thing that has 3/8 barb? Once I get this thing running well ill be rigging it
 
jerryjerry05

jerryjerry05

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The pump hose connector is one size.
If you can find an Johnson pump it might have the bigger barb?

90% of the time you can clean the carbs without anything added.
Depending on the bowl gasket, some are rubber some are cork.
The cork usually crumble as soon as you look at them.
I take the carbs off and turn them upside down and spray WD on the gasket.
Let it set over night, then loosen the screw and twist the bowl.
It might let loose? might not?
If it does let loose, don't try to remove it.
Just reuse it.
They aren't real expensive.

Depending on the crud in the bowl: that's how I determine if the welch plugs need removing and cleaned under them.

Most time a spray cleaner is all that's needed.

I also wash with Dawn soap and rinse with hot water and then blow dry.
Any spray cleaners and WD leave an oil on them and it can make them harder to start.
 
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Stokes760

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Quick question when rebuilding fuel pump do i just need to replace diagram and gasket or do i need to take further appart
 
jerryjerry05

jerryjerry05

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Floats,needles and seats.
The original floats were the best, aftermarket(usually white plastic) were junk and couldn't be adjusted.

Needles: there are 2 types. One is solid metal, the other is metal with a rubber tip.

Seat there are 2 styles used, one is a solid brass(rubber tipped needle) the other is brass with a rubber seal in the bottom (solid needle)

Some needle/seats can be replaced but if not really needed??? DON'T remove. You can ruin the carb body if not careful.

Carb sprays and carb soaks: The spray can be used just don't let it set in the seat with the rubber seal.
The soak: it can destroy the rubber tip and seat.

Also the seat with the rubber seal, the seal can swell and shut down fuel delivery when some carb cleaners and additives are used.

Depending on the pump, just the diaphragm needs to be changed.
The older style the one shaped like an 8 the valves don't usually go bad.
I've only seen one bad one in 30+ years.
 
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Stokes760

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jerryjerry05 said:
Floats,needles and seats.
The original floats were the best, aftermarket(usually white plastic) were junk and couldn't be adjusted.

Needles: there are 2 types. One is solid metal, the other is metal with a rubber tip.

Seat there are 2 styles used, one is a solid brass(rubber tipped needle) the other is brass with a rubber seal in the bottom (solid needle)

Some needle/seats can be replaced but if not really needed??? DON'T remove. You can ruin the carb body if not careful.

Carb sprays and carb soaks: The spray can be used just don't let it set in the seat with the rubber seal.
The soak: it can destroy the rubber tip and seat.

Also the seat with the rubber seal, the seal can swell and shut down fuel delivery when some carb cleaners and additives are used.

Depending on the pump, just the diaphragm needs to be changed.
The older style the one shaped like an 8 the valves don't usually go bad.
I've only seen one bad one in 30+ years.
Click to expand...

I soaked the carbs in chem dip while I was at work. The floats were blabck plastic. Needles were solid tiped stainless. And i didnt see any rubber seal in the seat. Ill try to get a better look I ordered the needles and rubber seats from that part number you had in other thread. What float height should i looks for?
 
jerryjerry05

jerryjerry05

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The rubber seals are VERY tiny and hard to see.
The float height: carb upside down. the float should be level.

Just hope the soak didn't eat the rubber seat.
Sometimes the chemicals swell the rubber, if anything hope that's what happened.
The swelling goes down after you wash the carb in soapy water and let it set over night.

Like I explained the seat might not come out of the carb body.
Many have ruined the carb by trying to remove them.

Post a pic of the new parts, set them next to a ruler so I can see the size.
 
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Stokes760

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Finished the carb rebuild and fired her up. Needs a little throttle to idel. Head felt a little too warm for my liking so killed it and decided to check t stat. Broke the bottom two bolts tryed all my usual tricks still broke. Quick question I had slotted booths up top and 11mm hex on the bottom. I was woundering stock hardware was the slotted bolts like i had on top? Bolts broke off flush and I need to drill out. And hope I can use the top holes as a depth gauge. Any info will help.
 
jerryjerry05

jerryjerry05

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The 87 came with 2 different screws.
1/4-20X 1 1/4"
Then a slotted screw 1/4-20X 3/4"

They are both a PITA to get out.
I worked on one for 3 hrs. and managed to break only one screw.
I replaced all 4 with hardened hex head bolts.
 
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