I need some help with a 1987 50HP Force

[chosos]

Re: I need some help with a 1987 50HP Force

I have not checked the compression yet. What value does it need to have? I'll try and grab the tester from Autozone on the way home from work tomorrow.

 

[chosos]

Re: I need some help with a 1987 50HP Force

These are what is in my carb. Granted, there is also the needle under the float, a spring on the float, and 2 brass jets. I did not remove the float, because it was a huge PITA to get that spring set last time i took the float out.

 

[Frank Acampora]

Re: I need some help with a 1987 50HP Force

I like to pull the plugs and squirt about a teaspoonful of premix right into the cylinder and replace the plugs and wires. This will flood it but with cranking, it will clear itself and fire. Then, if it stops after a few seconds, it is not getting fuel.

 

[Frank Acampora]

Re: I need some help with a 1987 50HP Force

By the way: When you invert the carb, the weight of the float will close the needle AND The float should be parallel to the carb body casting.

 

[chosos]

Re: I need some help with a 1987 50HP Force

im not following exactly. i think the float is working. I'll try and spray some premix in there, too.

I just wish i knew why my fuel isnt getting past the carb. I have that whole thing cleaned out.

 

[jerryjerry05]

Re: I need some help with a 1987 50HP Force

gustafsonerik posted a question yesterday about a manual for these motors. Read this and it has a link to a site that has a section on setting the floats.The first section has what you need.
If your not getting gas to the cylinders then the float/needle/seat ain't lettin it through.
I had trouble with one of my engines starting sometimes and I learned that tilting it all the way up and then pushing in the choke and turning it over it would let the float move and fuel would flow and it would pop/sometimes it would start in that position(make sure you shut it right off).As soon as it pops then shut it off and try after you put it down.Sounds drastic but I couldn't ever figure it out.I rebuilt the carbs and went through them a few times.But the tilt trick always worked.
I'll look and see if I have that spring.If I don't it's still available from boats.net
Swollen rubber in the F/N/S will stop you dead.J

 

[chosos]

Re: I need some help with a 1987 50HP Force

awesome! the manuals are nice. However, they did confuse me a bit because one shows a spring in the bowl for the main nozzle, and one doesn't.

Can anyone confirm is a WE-13 628061 supposed to have a spring in the bowl below the main nozzle?

also, is the main nozzle supposed to be pined against the carb body and idle tube? otherwise, my idle tube might be bent a bit, because it does rub against the main nozzle.

[edit] it also looks like i put the float spring back on backwards. will that spring really make a huge difference?

Now, on to the fuel pump - should the diaphragm be stretched or straight? My diaphragm has a bowl like shape. if its supposed to be straight - where can i get a new replacement?

 

[john from md]

Re: I need some help with a 1987 50HP Force

I have seen carbs with springs and without. If you go to www.mercruiserparts.com or www.dougrussel.com or www.crowleymarine.com, you will be able to put your model number in and get a schematic for your engine. You can also buy your parts from any of those places.

The idle jet will rub and is not easy to take out. Leave it alone and just spray it with carb cleaner.

The spring on the float must be replaced correctly or it will not function correctly.

The fuel pump diaphram should be flat. Buy a new diaphram and gasket, they will run you about $5 total.

Regards,

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

i installed the spring correctly on the float, but it is so weak, i cant imagine it helps any. i cant even feel it doing anything.

ill also pick up a new diaphram. could that be causing my fuel issues?

 

[john from md]

Re: I need some help with a 1987 50HP Force

The spring is weak but is designed to keep the float from bouncing not to stop it from moving.

If you are getting some fuel to the carb, my gut feeling is your problem may be more related to compression or damaged reeds. If you don't know how old your diaphram is, you should change it anyway.

Your compression should be 125 to 150 PSI.

Have you tried starting by spraying pre mix into the carb? It should at least kick a few times when you do that and your plugs should get wet.

Regards,

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

i'll read up on the reeds and check those today. i'll also order a new diaphram, because the old one was really bowed. i mean it probably stuck out 1/8".

I didn't get a chance to grab a compression tester, so I'll grab one today.

 

[john from md]

Re: I need some help with a 1987 50HP Force

Reeds are located in a plate bolted onto the crankcase behind the carb. The reeds are actually thin metal, or composite on newer models, strips that seal the the airflow to the carb while at rest. When the pistons start moving, the reeds open to allow a fuel/air mixture into the crankcase and from there into the ports to the cylinders. The reeds in a two cycle engine act somewhat like the valves do in a four stroke engine.

This is why compression is important to obtaining a fuel/air mix to the cylinders. If the compression is too low, the reeds won't be opened and you will not draw fuel into the engine.

Reeds are usually damaged from either overrevving the engine or from the engine backfiring violently. Overrevving occurs when you spin a prop hub and don't pull the trottle back fast enough, jump waves without pulling the power back or from running the engine on the muffs in gear. Backfiring occurrs from a lean mixture or improper timing. If your engine runs out of fuel at WOT, it will backfire and that may be enough to bend the reeds.

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

I went ahead and found a nearly new carb on ebay that I ordered. I figure with these no longer being made, it's probably a solid deal for 30 bucks.

So with that in mind, I figured I had nothing to lose and totally tore down my carb, removed the welch plug and all... i couldn't find anything jammed up, so in retrospect, it was probably fine. I also don't know if mine is or isn't supposed to have that spring under the main nozzle, so a new carb will solve that issue, too.

 

[john from md]

Re: I need some help with a 1987 50HP Force

Have you tried spraying some fuel in the intake and seeing if it fires? It doesn't need a working carb to light off and let you know if it is cabable of running.

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

so i can spray some premix in there with the carb off and if it fails to rumble, then its a compression issue or reeds? (if it has spark of course)

 

[john from md]

Re: I need some help with a 1987 50HP Force

If it will start or fire a few times, it will validate that the fuel delivery is the problem. It can be comression related, reed related, a vacuum leak somewhere (you don't have any rubber lines disconnected do you?), or carb related.

You can remove the reeds from the mix if you inspect them and find they are good. You can remove compression from the mix by performing a compression check.

Troubleshooting is always a process of elimination. When you narrow down the possibilities to a couple, then the process becomes for difficult.

Regards,

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

UPDATE - for the heck of it, i decided to take off the flywheel to inspect the points - they are all fouled up and one of them looks like it arc'd to the point where there is a pit on one side and an extrusion on the other. I'm gonna need new points for starters. I also need to test the condensors - hopefully that is in the clymers?

my clymers is here. I have been running through the pages, but im failing to see part numbers anywhere.

The points for this motor - are they the same points as the F123292 for a mercury? i also saw that a company named sierra makes these. is $50 for the set of points about normal? Is there anyone who has these on stock without a 3 week waiting period from the warehouse?

http://www.go2marine.com/product.do?no=96037F

i found this here with condensors for 88
http://www.maxrules.com/fixchryslerpoints.html#185162

or i can get these for 15 bucks...
http://cgi.ebay.com/ebaymotors/Forc...at_Parts_Accessories_Gear&hash=item35a46d7339

my plastic arm supporting the contact is cracked. i need to replace mine.

 

[pnwboat]

Re: I need some help with a 1987 50HP Force

You can also try this site. I would call to verify availability.

http://www.boats.net/parts/search/Merc2/Force/50%20H.P.%20%281987%29/507Y7A/ALTERNATOR%20AND%20ELECTRICAL%20COMPONENTS/parts.html

 

[john from md]

Re: I need some help with a 1987 50HP Force

If you go to the three sites I gave you before, you can enter your engine model and it will give you a parts schematic and part numbers. Parts are cheaper on line than through boat stores.

John

 

[chosos]

Re: I need some help with a 1987 50HP Force

boats.net seemed to have it all the cheapest, so i went that route - picked up the 2 points and the diaphram.