150 HP needs too long to warm up...........

[pyson]

I have @1992 Force 150 HP engine that I bought about 2 months ago. I have had it in the water a handful of times and each time the engine needs about 20+ minutes to warm up before it will accelerate without me having to hold the automatic choke in.

It starts ok, but cuts out as I try to increase the throttle. If I apply the automatic choke, the engine perks up and accelerates. After 20 minutes or so, the engine runs great---it responds well to the throttle, and idles perfectly.

Is this normal? I know older 2 cylinders need to be warmed up, but 20 minutes seemed like a lot to me.

Any suggestions would be greatly appreciated!

Thanks,

Matt

 

[pnwboat]

Re: 150 HP needs too long to warm up...........

You say you have to choke it to get it going? Sounds like it may be starved for fuel. Change both fuel pump diaphragms.

 

[pyson]

Re: 150 HP needs too long to warm up...........

I have an inline fuel pump (previous owner put it in). I checked the fuel line--and it seems to be delivering a steady stream of gas.

Plus.....it works fine after warming up for 20 minutes........so any line blockages would remain constant wouldn't they?

I agree though.....it seems fuel starved.

 

[pnwboat]

Re: 150 HP needs too long to warm up...........

Are the original fuel pumps still hooked up or are they by-passed? If the original fuel pumps are not by-passed, you may still have one or both with bad diaphragms.

Anyways, maybe you have low battery voltage?? I assume the in-line fuel pump is electric? You may have low voltage initially until charging system brings battery voltage back up?? Check your battery, it may need to be fully charged or may be on it's last leg. Just a thought.

It always concerns me when I see something that someone has added. A lot of times this just masks the real problem. There should be no need for an additional in-line pump if original pumps are in good working order.

 

[john from md]

Re: 150 HP needs too long to warm up...........

Have your carbs ever been removed and cleaned?

John

 

[pyson]

Re: 150 HP needs too long to warm up...........

1. Battery is brand new--bought it 1 month ago.
2. Not sure about "original fuel pumps". Past owner said he replaced the primer bulb with this inline fuel pump. Line runs from gas tank to inline fuel pump and then into the motor---what else should I be looking for?

3. I have not cleaned the carbs since I bought it 2 months ago. Not sure even how to do it......is it difficult?

Matt

 

[john from md]

Re: 150 HP needs too long to warm up...........

Most of us don't like inline pumps for several reasons. The most important is that they keep pumping until their power is removed. If you break a line, your boat becomes a potential bomb.

The diaphram pumps on the engine are more than adequate. The previous owner was probably have problems and didn't know how to trouble shoot them.

In recent years the check valves have started sticking due to the alcohol in the fuel. You have to be mechanically inclined to change them. The same goes with cleaning and rebuilding the carbs. The fuel diaphrams themselves are easy as there are only six bolts and three hoses to remove.

Are you handy?

John

 

[Frank Acampora]

Re: 150 HP needs too long to warm up...........

I think that if it runs fine after an extended warm-up, you possibly may have the low speed needles set too lean on one or more carbs. This is a critical condition that needs to be checked before any further running is done. I would also ceck the float levels. Especially, since you have 5 cylinders, a couple running correctly may mask the ones set incorrectly. Yeah, the engine is running now, but it is trying to tell you something.

Explanation: At start, off idle, and during acceleration, the colder an engine is, the more fuel it needs to have enough vaporized fuel to give 14 -16 to 1 ratio. As it heats up, the fuel vaporises quicker and better and the 16 to 1 ratio is more easily acheived. HOWEVER: Hot engines will easily run on mixtures greater than 16 to 1 which will cause detonation. Just because the engine runs does not mean it is correct.

One of the symptoms of a too lean setting on the low speed needles is "sagging" or possibly even stalling during acceleration. By holding in the choke you are artificially enriching the mixture.

 

[pyson]

Re: 150 HP needs too long to warm up...........

John--do you concur with what Frank is saying? You sound very knowledgeable Frank--so I am thinking of taking the motor in and having a local boat Dr. take a look at it. I will mention the problems--and what you said in your post

I hope this doesn't cost me an arm and a leg!

Thanks so much guys.

Matt

 

[john from md]

Re: 150 HP needs too long to warm up...........

Your question is like asking an intern if he agrees with the chief of medicine!

Frank is the guru as far as Chrysler Force is concerned and you can take what he says to the bank.

As to expense, boat mechanics charge high prices and may not be too familiar with these engines. It is always better to do for yourself with these older machines. I understand that not everyone has the abilities to do such work.

However, do you have any friends or relatives that have motorcycles? If a person works on his own bike, he could rebuild these carbs and replaced the fuel pump diaphrams with no sweat.

If you are handy with tools at all, we can talk you through it with the help of a manual.

Regards,

John

 

[pyson]

Re: 150 HP needs too long to warm up...........

My local marina charges $75 an hour labor!

I have virtually no experience in motor repair, have no close friends who work on motorcycles and do not have the owner's manual for the engine. I imagine this means being able to adjust the low speed needles and checking the float levels would not be something that I could do then?

 

[john from md]

Re: 150 HP needs too long to warm up...........

Unfortuneately, if you are not mechanically inclined, you can do more damage than good.

I suggest next time you purchase a newer engine with a warranty.

John

 

[pyson]

Re: 150 HP needs too long to warm up...........

Thanks for your help. I did bring it in today to the marina. He said he thought it sounded like the low speed needle Frank mentioned.

I knew going into this investment that there would be money that needed to be allocated to repairs, so I am not crushed by any means by this.

We will see if I feel the same way if he comes back with a $500 bill.

Matt

 

[pyson]

Re: 150 HP needs too long to warm up...........

Well Frank and John, I just got my boat back and the bill---and got good news.

The shop said that all was needed was a carb adjustment (two screws?--I think this is what you mentioned). He gave it a test run and said it was running well.

Final bill----$35.

I was pretty happy with that--obviously!!!!

How does that sound to you guys? Sound about right?

 

[john from md]

Re: 150 HP needs too long to warm up...........

If he adjusted the idle mixtures and it runs fine then that settles it. Enjoy your summer.

John