1998 Force 90 ELPT by Mercury Marine

[dbmacboat]

Hi guys,
Took my boat to a marine shop in late spring to have them check things over and make sure ready for summer.
They called back and said compression was 1. 130 2. 130 3. 125.
Spark was good.
They ran it and couldn't keep it running under load (dyno) so they rebuilt fuel pump and restart. Still same problem, so they took off head and inspected cylinders, found orange varnish on cylinder walls 1,2,&3.
They also said fuel pump had zero vacuum.
Final conclusion was engine needs rebuild.
They said parts would be scarce and cylinders would have to be rebored and new piston rings plus work on exhaust.
I talked to another marine shop for a second opinion and it seems the Force lineup is almost a swearword in the industry. They agreed with the first marine shop mechanic and said sell the engine for parts and get what you can.
Strange that I had it on the water last summer, it worked fine, lots of power, 45 mph on the water trimmed out and I know it doesn't compare with being in the water but I can put the muffs on in the yard and it starts, idles and runs through varying rpm.
I can't ethically sell it to someone knowing the mechanic's conclusions.
Any opinions on parts availability, their final conclusion?
So looking at a rebuild, or finding another used/good engine, or new, which is very expensive (100-200 per HP in Canada) or.... other thoughts and opinions very much appreciated!
Thanks,
Dennis

 

[racerone]

Your location?----The compression values indicate that there is hope for the motor !----I would look for another shop.----Could be an issue with reed valves for one cylinder.----Remove bypass covers for inspection of pistons rings.----It sure seems like a simple issue was overlooked by these shops.----And most are interested in customers who are an easy source of revenue.

 

[topgun3690]

Your compression numbers are a little low but pretty even across the board. If the cylinders aren't scored/damaged then not sure a rebuild would be necessary. Bottom line on these engines.....you really have to do your own work on these....nobody around here would even look at an old Force or Chrysler, and if they did they would bend you over on labor costs.

If doing your own repairs is not an option, I would seriously consider getting a later model engine that a shop would work on and parts availability was better.

 

[racerone]

Posting pictures of boat / motor and video of it running may help you get help !

 

[topgun3690]

Posting pictures of boat / motor and video of it running may help you get help !

Don't think they have fixed the posting pics problem yet on this forum.......

 

[topgun3690]

Before condemning the motor, do as racerone suggested.....open it up and take a look at the cylinders and pistons. Pics currently can't be loaded on this site for technical reasons but you could make a youtube video showing the internals/engine running, by posting the link on here. No money spent doing that either, just your time. If there is no internal damage, the good news is the engine does run.....you got compression and spark. Might be a simple fix. You won't know until you dive into it a little bit.

These engines have a bad reputation, deserved or not.....which makes them pretty cheap to buy and maintain. With proper maintenance they perform well. You just have to be willing to get your hands dirty and DIY. With a good factory shop manual and this forum, you could do the work yourself and avoid getting "plowed" by some shady repair shop.

 

[dbmacboat]

Your location?----The compression values indicate that there is hope for the motor !----I would look for another shop.----Could be an issue with reed valves for one cylinder.----Remove bypass covers for inspection of pistons rings.----It sure seems like a simple issue was overlooked by these shops.----And most are interested in customers who are an easy source of revenue.

Hi, thanks for the reply. My location is in Saskatchewan Canada, just outside of city of Saskatoon. I talked to another shop today and got a totally different story. ( lots of parts available, Force by Mercury Marine not so bad, optimistic about it, etc...) so I took it there today.
Will see what they say in a week or so. If their cost is prohibitive, I'll attempt it myself. I have a buddy who is a mechanic (not a marine one) but he'll know his way around cylinders, pistons, rings, reed valves, etc..
Thanks again for your reply!
Dennis

 

[dbmacboat]

Before condemning the motor, do as racerone suggested.....open it up and take a look at the cylinders and pistons. Pics currently can't be loaded on this site for technical reasons but you could make a youtube video showing the internals/engine running, by posting the link on here. No money spent doing that either, just your time. If there is no internal damage, the good news is the engine does run.....you got compression and spark. Might be a simple fix. You won't know until you dive into it a little bit.

These engines have a bad reputation, deserved or not.....which makes them pretty cheap to buy and maintain. With proper maintenance they perform well. You just have to be willing to get your hands dirty and DIY. With a good factory shop manual and this forum, you could do the work yourself and avoid getting "plowed" by some shady repair shop.

Hi, awesome, thanks for the reply. I'll consider the video thing, when it comes back from the third shop. They are gonna look at it. If too pricy I'll do it with my mechanic buddy.As per my reply to racer one. Will have a lot of time over the winter to do it.
As always this forum is awesome!
Thanks again for the reply!
Dennis

 

[jerryjerry05]

It sounds like the first 2 shops were afraid of the Force???
Zero vacuum on the pump: B*&^#$%T if you had compression you had to have vacuum to operate the pump.
The compression was probably done wrong or used a Harbor Freight compression tool.
They just didn't want to mess with it.
They should have refused it at the door.
Sounds like the last guy knows and isn't afraid.

 

[racerone]

????----You can have compression in the cylinder.-----And that does NOT mean that there is compression in the crankcase !----You could have ZERO compression due to a broken reed valve or hole in the crankcase !----Fuel pumps operate on crankcase PRESSURE and not vacuum.

 

[dbmacboat]

????----You can have compression in the cylinder.-----And that does NOT mean that there is compression in the crankcase !----You could have ZERO compression due to a broken reed valve or hole in the crankcase !----Fuel pumps operate on crankcase PRESSURE and not vacuum.

 

[dbmacboat]

So I got a call from the third marine shop today saying that they were done with my boat engine and that its working fine.
I asked what they did, he said well, checked compression and spark and that was good, he said they went over the fuel system and fuel supply ( tanks, hoses)
He said they made some carb adjustments so the carbs (3) were synchronized and then ran it under load and it worked fine throughout the range, They also ran it before they made the changes for comparison.
Almost a complete 180 from the first Marine shop. But real test is on the water, so will see this weekend if it truly is ok.
Anyways, as always thanks guys for your help!
Dennis

 

[topgun3690]

Aint it amazing, 2 shops said the motor was toast......the third one did some basic carb work, and said it was good to go.......hopefully your next outing on the water confirms it really is fixed. Good luck.

 

[dbmacboat]

Aint it amazing, 2 shops said the motor was toast......the third one did some basic carb work, and said it was good to go.......hopefully your next outing on the water confirms it really is fixed. Good luck.

Well, took it out on the water started and ran fine. Up the lake and back, did some fishing, basically had it out all day. 46 mph all trimmed out on the lake, same as it ever was.
Took a video and will present to the shop that diagnosed engine as "needing to be rebuilt".

 

[racerone]

See post #2 on this.

 

[The Force power]

See post #2 on this.