1987 Saltare' running hot

[skiman_61]

Hey Gentlemen,

My salt is running about 180-200 at higher rpms, 3000+, Stays 160 or below at 1200. Fresh impeller, checked all the hoses and the thermostat housing for obstuctions. Will have to order a new thermostat as none local. PCM, 454. Anything I'm missing?

Thanks,

Jack @ Cumberland

[NorCalPR]

Only thing I can think of off the top of my head to check for is a smooth impeller housing, and a stiff intake hose (it could be collapsing under higher speeds)

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[cadunkle]

Indeed the impeller housing can be worn with grooves in it. Also check the wear on the front plate. I believe these are reversible but new plates are also available for cheap.

[Salty87]

Do you have a sea strainer? If not the transmission cooler may have some blockage.

Check the belt, too. Could be slipping.

[skiman_61]

Do you have a sea strainer? If not the transmission cooler may have some blockage.

Check the belt, too. Could be slipping.

The housing is smooth. I'll check the strainer again and I'm gonna replace the belts if only because I can't remember when I last did so. They look fine, but there is some dust. Had one snap years ago. Quite a noise.

The lake is up, and full of debris of all kinds. Thanks again for comments.

[wotan2525]

Once you confirm that you have good water flow and that the thermostat is opening, the only other thing it could be is that your raw water pump is due for a rebuild. I chased this problem around on my 1987 for about a year before I rebuilt the water pump. Fixed the problem immediately. I never knew that they had an expected service life.

[skiman_61]

Once you confirm that you have good water flow and that the thermostat is opening, the only other thing it could be is that your raw water pump is due for a rebuild. I chased this problem around on my 1987 for about a year before I rebuilt the water pump. Fixed the problem immediately. I never knew that they had an expected service life.

There was some crap in the transmission cooler. Not a lot, but some. I had checked it when I put the new impeller in, so I didn't think to look again. Lake test on the 23rd, we'll see.

[skiman_61]

There was some crap in the transmission cooler. Not a lot, but some. I had checked it when I put the new impeller in, so I didn't think to look again. Lake test on the 23rd, we'll see.

Still getting hot at higher RPM. Haven't replaced the thermostat, but I don't think that's the issue.

[Jetlink]

Still getting hot at higher RPM. Haven't replaced the thermostat, but I don't think that's the issue.

How hot are you talking now and where are you measuring again?

[skiman_61]

How hot are you talking now and where are you measuring again?

Gets up to in excess of 200 on the temp gauge. Cools off back to 160 when I slow down.

Vince at SkiDM called me back yesterday. Described methods to tests the pumps I wouldn't have thought of. Also advised I check the exhaust as the baffles catch debris and could be the issue.

[Jetlink]

Do you have mufflers or the "Super Trapps" on the transom of your boat? Are you taking temperature readings all around the engine as well or just going off what the gauge is telling you at the helm?

[skiman_61]

The traps/baffles. Just at the helm.

[Jetlink]

I would go ahead and get one of those small infrared thermometers from Harbor Freight and start taking measurements from various places on the engine and at various throttle settings and see what you get.

[skiman_61]

I would go ahead and get one of those small infrared thermometers from Harbor Freight and start taking measurements from various places on the engine and at various throttle settings and see what you get.

I presume to be seeing multiple temps depending on placement, ya? Pulled the thermostat out. 20 degrees cooler overall. Still getting to plus 200.

Where are the drain plugs on the block? Thought i knew, not sure what I'm looking at.

Betting on the circulation pump. Raw water tested today. H2O a plenty coming in. Thirty year old boat, that mechanism has never been off since ive had it.

[middlegriff1]

There is one on each side of the motor midway back right above the oil pan.

[cadunkle]

If you've confirmed good water flow from the raw water pump through the engine and no obstructions or accumulation in the block, manifolds, or thermostat housing... I'd be pulling the circulating pump (regular water pump) on the engine. Could be a bad impeller in it, maybe an automotive replacement and the impeller rusted away.

[skiman_61]

If you've confirmed good water flow from the raw water pump through the engine and no obstructions or accumulation in the block, manifolds, or thermostat housing... I'd be pulling the circulating pump (regular water pump) on the engine. Could be a bad impeller in it, maybe an automotive replacement and the impeller rusted away.

Thanks sincerely for all the help. I pulled the raw water pump again and found an obstruction. I'll explain once I figure it out. Recall I previously pulled all the water lines and found them to be clear subsequent to replacing the impeller. Haven't put the pump back on yet. I'll report back. Hope this fixes it.

[skiman_61]

There is one on each side of the motor midway back right above the oil pan.

Thanks. Also, staring at the block I see that the firing order is in the casting on top of the motor. Almost 20 years I've been fooling with this thing and never noticed that.

[skiman_61]

Happy 4th, everyone. Safe boating!