Force 125 Cooling system question

[reelfishin]

I just picked up a used, 1987 Force 125, it has trouble getting water up when first started. It had just came from a local dealer after having a new impeller installed.

I pulled the thermostat, it looks pretty crusty so I ordered another one with a new gasket. It will be next week before I see it.

My question is, with the T stat out, it pumps water almost instantly from the two exhaust holes in the mid section, but no water ever reaches the thermostat hole. (The motor had just come in from a 40 mile or better run when I pulled it and took it home, but I noticed it didn't have any water pumping from the exhaust bypass holes when it was running the head seems to stay moderately cool but it was getting pretty hot before it began to cool.

(I'm used to having OMC outboards with a definite tell tale stream. Once warmed up and running the motor runs great, the head remains cool enough to lay your hand on. Not sure what they did in all when it was in for service, but there was a doggy bag with an old water pump impeller and kit along with a set of used plugs, and an old fuel pump cover and diaphragm.

Will a stuck thermostat prevent water flow in one of these?
is stop tell tale water from being emitted from the upper exhaust ports?
When it was in the water on the old boat, it was pushing water pretty good from the upper ports, but in a barrel it barely moves any water for the first few minutes, and never when running on a set of ears and a garden hose.

 

[maxum247]

Re: Force 125 Cooling system question

My 1989 125 Force sprinkles a stream of water from the exhaust holes while on muffs.
Without the thermostat in and the boat the water, it funnels water out of the exhaust holes in a constant flow, with the thermostat in it's a consistant spray.
If you see white steam and little or no water with the thermostat replaced she's running warm and getting hot.
I've heard of a couple of Force outboards that wouldn't pump on muffs, why I'm not sure.

max!

 

[john from md]

Re: Force 125 Cooling system question

Reelfishin,

First of all, the Force engine will not run properly without a thermostat. It suffers from too much thermal shock which increases the stress on the engine. Stress is cumulative and the engine will fail earlier because of it.

As for pumping water, my experience with the 85's and 125's is that they take a minute to start pumping water. If you make a telltail, you can almost time it when it comes out. I believe this is because it has to pump out the water up from the pickup and pump the air above the impeller out of the engine.

It is easy to make a tell tale for this engine if you want, just search for telltale. The block has a plug just behind the thermostat that is used for the telltale supply.

Don't forget to put that thermostat back.

John

 

[reelfishin]

Re: Force 125 Cooling system question

I had some trouble getting the bolts out for the thermostat but finally did get it off. I ran it only for a minute or two on the ears to see if the impeller was pumping or not. Not having seen any sign of water after a few minutes and not being too familiar with these, I wanted to make real sure it was pumping water.
With the stat housing off, it pumps water out the upper exhaust holes, but it never gets up to the thermostat hole. If I pour water in the stat hole, it runs out the center of the prop, so nothing is clogged. My concern is that it's not pumping enough water but I'm not sure that running it on a pair of ear muffs or in a bucket will supply enough water to fill the block as it would in the water.
Keep in mind that the boat was driven pretty far with no overheating right before it was pulled out. I just want to be sure there isn't a problem before running this any distance.
I do realize that due to the obvious salt corrosion on this motor it's probably not long for this world, but not many older motors are around here. Its been stored in the water and has been in use since new. I rode with the former owner when we brought the boat back to be loaded on the trailer and it ran fine and the head was only warm to the touch after a few hour ride. It was warmer than my Evinrude would have been but not by much. (Not enough to be really uncomfortable to hold your hand on. I'd guess maybe 120 or so degrees). I did notice that the plug boots, which are new, will zap you if you get anywhere near them. The coils, wires and boots were just changed, yet they will light you up if you get anywhere near them. I coated the boots and wires with some dielectric silicone grease for now for no other reason than to stop getting hit with ignition spark. (The coils were OEM from Quicksilver, the old ones were still in the boat).
I am a bit leery about any internal salt corrosion but the motor looks good inside the stat housing, it's not eaten up at all around there. The anti cavitation plate and upper fin are pretty well gone, and the outer lower unit is well pitted.
I may put it in with the stat housing off just to see if I get water up there with the motor down. Seeing water get all the way up would make me feel a whole lot better about trusting this thing.

 

[john from md]

Re: Force 125 Cooling system question

Reelfishin,

If it was stored in the water, the water pump housing may be badly pitted. This will eat up impellers pretty fast and allow water to bypass the vanes.
You can pick up a complete rebuild kit with housing, plate,impeller etc from ebay for $50 plus shipping.

I have never had a Force engine that would not pump water with the proper muffs. The large muffs with the heavy spring steel arms are the ones to use. That said, you can also buy a large storage bin from Kmart for $19 that will also work. I flush both ways depending where the boat is parked at the time.

If you need a lower, you can pick them up off ebay for $200 - $300.

Regards,

John

 

[reelfishin]

Re: Force 125 Cooling system question

It will most likely end up needing a lower unit, but I'd like to see if it will finish out this season. I'm not sure that I'll keep the Force motor if it needs a lot of work. I'd rather hang something newer for reliability. If I hadn't run it without the stat housing on and not seen any water up there or had the trouble running it on the ears, I'd have never thought there was a problem.
I am using the round style ears, I couldn't get a good seal with the larger rectangle style. They seal pretty good but I don't have great water pressure here either. Its got a huge hydrofoil on it, otherwise I'd have run it in a barrel. I'm afraid to mess with the hydrofoil since the anticavitation plate is so corroded. My concern isn't so much the condition of the lower unit as it is in being able to get it back off.
I realize this thing is on borrowed time, but I'd like to get this fall out of it before tossing it for something else. I have a few other motor options here to use.
I just hate to give up on a motor if there's still some life left in it.

 

[wajajaja02]

Re: Force 125 Cooling system question

Had a lot of trouble on this topic, multi impellers, rebuilding the pump housing, finally a new pump, still no tel tale, so, a new head gasket, found that the first marina skip the thermostat, and it doesn't pump well on muffs, so I use a landscape barrel , runs well, and problems seem to be solve, just seemed to take time to get parts ,pump from merc.

 

[reelfishin]

Re: Force 125 Cooling system question

I took it to my shop today, I have much better water pressure there, with the stat out, it puts water out the upper exhaust pretty well. I'm still waiting for the new stat and gasket, so I can't tell on that yet. What bothers me is that even after ten minutes of running, there's no water showing at the stat housing even with the stat housing removed? There is some exhaust coming out but I assumed that's coming from down low. If I submerge the motor in the water, it pumps pretty well and I get flow up top, but not great. I'm thinking that with the cover off, it's not able to push the water up for some reason. Even in a 55 gallon barrel of water it won't pump water up to the stat. With the stat installed, (still the used one), it pumps water up to the plug on the top of the head, if I take out the stat, it won't pump water up there at all, or at least not enough to push anything out. I'm going to wait till I get the new stat, then take it down to the river and see what it does, if it don't overheat and it seems fine, its getting run like it is. If the problem is in the lower, I'm not bothering to fix it. It's just too old and too hard to get parts for. If I have to wait to get a stat and gasket, or even the impeller, I can't imagine what I'd have to go through for more major parts. I suppose I could find a good used lower, but so far I've looked at several parts motors, and everyone had blown lower unit. Most were totally grenaded or seized.
It looks like the 85 and up motors use the same lower? Direct swap?

Of course, something that's in the back of my mind is that if it was kept all year in the water, it most likely never got flushed, so if the lower unit is eaten, I suppose the rest of the motor is about the same or not too far behind. Chances are its not worth messing with.

( I have a Mercury that does the same thing, no tell tale stream in a bucket, even with a new pump, new tell tale hose and stat, but has strong stream when out on the water. It's been that way since new, and it's never seen saltwater and has no corrosion).