Idle rpm on 1975 185HP

[Randyg123]

An update on my engine.
I took my boat back to the mechanic that performed a tune-up and carb job back in March to have him make sure everything he did was fine. He checked the timing, link-n-sync, and all and said everything is great but he raised the idle up a bit.

The problem I have been having with my boat was that it would not idle but ran good at high rpm. Well, I finally got the boat out and found that he set the idle at 1100, out of gear, in the water. In gear, it runs at around 900. Lower it and the motor stalls. So that is all he did.

Is this idle too high? Will it damage my gears?

I plan on rebuilding my carbs later on this year but would like to use the boat until then. I don't know what this guy did, but the boat never ran well. He even tried to tell me my choke and throttle linkages were switched and was going to switch them back. I told him not to because they were correct as per the manual. But he insisted that they were wrong. So I don't have a lot of confidence that he went out of his way to perform a good job on my engine. Probably just slapped in a new carb kit and adjusted the linkage.

On a funny note, when I took the boat out, it ran okay, although hesitant to when throwing the throttle open. Did some fishing running from spot to spot across the lake. Then after about three 10-15 minute runs, the engine wouldn't start. I forgot to open the tank vent. The bulb was sucked flat and the tank partially collapsed. I think my fuel pump works well - haha

Thanks to all that have helped so far in my endeaver. I occasionally see persons out there asking for help and when they don't get the answer they want, they get mad. That's too bad for them.
Thanks again for your help so far and I know I will be bugging you all soon enough.

 

[ftltony]

Re: Idle rpm on 1975 185HP

On a funny note, when I took the boat out, it ran okay, although hesitant to when throwing the throttle open. Did some fishing running from spot to spot across the lake. Then after about three 10-15 minute runs, the engine wouldn't start. I forgot to open the tank vent. The bulb was sucked flat and the tank partially collapsed. I think my fuel pump works well - haha

I have mentioned this same problem I had when I was a kid. I had a 9.9 and ALWAYS forgot to open the vent and I would go out fishing with my buddy and when we were out in the middle of a lake, the engine would cut and die and both our hearts would stop until I remembered I forgot to open the vent!!!!

As to your idle, My 225 Ocean Pro is set at 1100 rpms at out of gear idle. I don't know if your motor has the same thing mine does but my motor has a circuit stops the motor from running for approximately 3 firings of the motor. It is called "shift assist" and it stops the motor from firing for 3 times when I put it into gear to stop the "bang" you usually get when you throw it into gear. Do you know if your motor has shift assist?

 

[cdoliver]

Re: Idle rpm on 1975 185HP

Have you checked your compression? If you have uneven compression, even if he cleaned the carbs the idle won't be smooth. that might be why he raised the idle rpm??? check your compression, and think about doing a decarb if you havent already. A decarb might even out compression if that is the problem. good luck.

 

[tashasdaddy]

Re: Idle rpm on 1975 185HP

if it won't idle you probably have clogging low speed jet. the problem is with the dirty jets, it is not getting proper fuel,, but it is not getting proper oil to lubricate it. i would do the carbs now. paying close attention to the jets remove all of them, clean and that a couple of pieces of stranded copper wire, and run thru the jets to be sure there is nothing in there.

why did he say the linkage was wrong.

 

[ezeke]

Re: Idle rpm on 1975 185HP

900 in gear at idle is too high. As TD indicated, it is probably nothing more than idle capillaries or jets being clogged, and will correct itself once the carburetors are cleaned and properly synchronized.

On that note, get a good inductive digital timing light and check the RPM. Your wrench may not trust your tachometer either.

 

[Dhadley]

Re: Idle rpm on 1975 185HP

Before going further we'll need to know what motor you have. There is no such thing as a 1975 185. There is a 1975 85 and a 1985 185.

Again - the shift assist works when coming out of gear not going into gear. At any rate none of the V4s nor the 185 had one.

900 in gear and / or 1100 in neutral is too high. That's not good on gears & clutch dogs.

 

[ezeke]

Re: Idle rpm on 1975 185HP

I thought that you might be referring to the 1975 135HP in earlier threads.

If you don't have a good fuel filter on the fuel system, the chances of continuously fouling your carburetors are excellent.

 

[Randyg123]

Re: Idle rpm on 1975 135HP

Re: Idle rpm on 1975 135HP

.........why did he say the linkage was wrong.

BTW Yes it is a 135 not a 185! Ooops


The linkage on the carbs is a one-piece part. The linkage on the chokes is a two-piece part that allows the two chokes to be syncronized.

The mechanic insisted that the choke linkage should be on the carbs so he can sync them. I explained to him the the carb syncronization is performed using the lower throttle adjusting screw as the manual described and the the only to sync the chokes is to use the two-part linkage. Just as described in the manual. He told me I was wrong and that he'd been doing this for twenty years...yada, yada, yada, but I insisted he kept them the way I had them.

I would assume from his comments, that it is quite common to have an adjustable link between the carbs on other engines and so in a generic sense, that is where the adjustable link should be - from his perspective. This meant to me indicated that he did not consult a manual for my specific model when he made the repairs the last time. We even argued over what the WOT timing should be. I told him 20 and he said these Johnsons should be set at 22. I told him to "look it up". He did verify that issue and aggreed that I was correct.

I know that with some many makes and models that it must be extremely difficult to keep up with all the different specs. Especially since those that will accept older motors typically do not specialize in a make (at least not around here). So I guess you can't have manuals for everything. In retrospect, next time I need to consult a pro, I'll bring my manual with the motor, unless a mechanic verifies that he has an OEM for my model.

 

[ezeke]

Re: Idle rpm on 1975 185HP

The synchronization of the two carburetors on the V4 crossflow engines was always done from the lower carb with the screw and adjustment lever like yours - right through the 1998 models. The throttle link was always one piece.

Even if a wrench does not have the manuals, he probably should know how to use a computer well enough to look at the parts diagrams that are free and on line.