1982 150 v6 loss of power

[rla0248]

A new problem has now surfaced. Last time out I was running in gear at a fast idle of about 1400 rpm. After about a minute the rpms went down to about 1200, so I increased throttle back to 1400 rpm. About 30 seconds later the rpms drop again. I figure it is probably a too rich carb problem fouling out plugs. So, now its time to quit idling around and get down the lake, WOT is about 1600 rpm. I leave it WOT at 1600 rpm for about 20 seconds and then all at once it clears up and runs great. At that point I'm thinking that probably have some carbs flooding at idle.

That evening I pull and clean the plugs. Next day the same thing happens, but it never clears up. WOT = 1600 rpm.

Unless you guys have other suggestions, I will be pulling the carbs.

 

[KCLOST]

Re: 1982 150 v6 loss of power

Check spark and compression, is both are good you have a fuel problem....

 

[MortenH]

Re: 1982 150 v6 loss of power

The fuel problem may also be the primer bulb or the fuel line. Happened to me and killed my beast.

 

[rla0248]

Re: 1982 150 v6 loss of power

Spark on all six and compression on four cylinders is 123 -126, and 140 on the other two.

 

[rla0248]

Re: 1982 150 v6 loss of power

Does anyone know where I can get a set of used carbs? What different years and models might interchange? Last night I removed the carbs. The main jet plug broke off on one of them as I tried to remove it. I was able to remove the main jets from only one of the carbs. All the others are stuck. Tonight I will spray them with deep creep and see if that will unstick them.

The carb that I could get the main jets out of had two different size main jets on each side. One jet was at least twice the diameter of the other one. One jet is stamped 060 and the other 056 (I think), but one has a tiny hole and the other a least twice the diameter.

All six floats are cracked and spliting.

 

[studlymandingo]

Re: 1982 150 v6 loss of power

The cracked floats is probably your issue there.

 

[rla0248]

Re: 1982 150 v6 loss of power

Hi, found a set of used carbs from a 1989 XR4. I disassebled them and they were very clean. I installed them last night and I'll see tomorrow how it rums with these carbs.

Does anyone have any experience with a change like this or have any comments.

The carbs are very similar, but the throttle bore is larger, with corresponding larger jets. The throtlle bore is exactly the same diameter as the reed plate manifold. The original carbs were smaller diameter than the manifold bore.

Also these carbs use an enrichment system rather than a choke plate for cold starting. What is the starting procedure for this system? I have removed the choke solenoid and hooked the wire for the choke soleniod to the enrichment solenoid.

I would assume that I would hold the key in for a period of time to allow fuel flow to begin before cranking. If that is correct how long would you suggest for my first try? 5 seconds, 10 seconds?

 

[studlymandingo]

Re: 1982 150 v6 loss of power

Usually just a few seconds on the enricher valve. May have to do it once or twice in order for it to get going.

Have you run her yet with the new carbs?

 

[rla0248]

Re: 1982 150 v6 loss of power

OK,

I ran it this weekend with the XR4 carbs. It seems to run great. Starts quicker and idles better. Gets on plane quicker. Seems to have more power.

But!!!!! I ran about 3 miles down the lake to my first fishing stop. Fished for about 2 hours. Motor restarted instantly, but seemed to be running on about 3 cylinders. Fished the rest of the day idling around and using the trolling motor.

Saturday night I removed and cleaned the plugs. Sunday morning, the motor started and ran great. I ran about 5 miles down the lake to a different fishing spot. Fished about 2 1/2 hours. Restarted the motor and again appears to running on about 3 cylinders. Limped around on 3 cylinders all day.

Any Ideas? Now I'm beginning to believe that the problem is ignition. The last time I checked (about 4 weeks ago) it was getting spark to all cylinders.

I guess I will have to check spark when it is acting up, not cold in my driveway.

 

[rla0248]

Re: 1982 150 v6 loss of power

I tested the stator and trigger, per mercury manual last night and both check out good. I'm getting spark to all six cylinders. Spark tester is set a 1/2 inch.

It seems to be an intermittent problem.

I'm pretty sure that ignition is the problem. Any ideas on the most likely cause of the problem.

A couple of months ago, I had switch box problems. I bought a used pair of switch boxes and then it seemed to run OK for a while.

 

[akendall]

Re: 1982 150 v6 loss of power

I tested the stator and trigger, per mercury manual last night and both check out good. I'm getting spark to all six cylinders. Spark tester is set a 1/2 inch.

It seems to be an intermittent problem.

I'm pretty sure that ignition is the problem. Any ideas on the most likely cause of the problem.

A couple of months ago, I had switch box problems. I bought a used pair of switch boxes and then it seemed to run OK for a while.

rla0248 - sorry to interupt your thread with this question - but where did you get your spark tester?

 

[phatmanmike]

Re: 1982 150 v6 loss of power

any auto parts store.

 

[rla0248]

Re: 1982 150 v6 loss of power

I think that I may have found the problem. When I got these used carbs, I pulled the bowls off each of the carbs and each seemed to be clean, so I installed them.

Last night I disassembled them again and some of the floats are heavier than the others. Even the lightest of them seems a little to heavy to me.

Anyone know what the weight of the floats should be? The heaviest two weigh about 11 grams and the lightest weigh about 8 grams.

Anybody know where I can purchase new floats? Mercury dealer says the part is discontinued.

Thanks.

 

[studlymandingo]

Re: 1982 150 v6 loss of power

How have you made out on your problem?