Help! Cooling issue! Novice

John,
One you get the new impeller in, I have a feeling you will still need to go after the cooling problem.

Tim mentioned it earlier, tighten all the hoses on the suction side of the RWP. You may be sucking a small amount of air.

John,
What about the RWP? have you taken a look at the impeller? I'm curious if it's bad or good.

Atomic Dam wrote: 8122pbrainard wrote: John, It will probably give you most information you need for your engine. Take a look and if you need more, ask and we'll see if we can help. The boat actually came with this manual. As much as I have looked through it, it doesn't have anything in there about the escort produced 351. I appreciate you sending that over anyway though.

John,
What else are you looking for? The Escort is basically the same as a early PCM 302/351.

Have you opened up the RWP yet to take a look? Maybe I missed it?

Okay, So here is the site that I got the correct Jabsco part number from. It requires precise measurements of the existing impeller to find the part number for your replacement. After getting the part number and doing a search online, I found that this also has a corresponding Mercruiser part number.

https://pdf.directindustry.com/pdf/jabsco/impeller-replacement/14649-391577.html

The Mercruiser cross reference number is MERCRUISER 34765A1 500106 / JABSCO 920-0001

I found one locally for $80, but decided to order them online. It was on amazon for $20. When it comes in, I will confirm that it was indeed the correct part, and update this thread.

John,
Here's a link to the eary PCM 302/351 manual that's in the reference section. It will probably give you most information you need for your engine. Take a look and if you need more, ask and we'll see if we can help.

Sorry that seemed strange, unintentional. I will do that straight away. Im away from the house, i am replying from my phone. Will post more info when i get to my computer.

Through a thorough cleaning, I actually found a faintly printed part number on the one of the blades of the impeller. I typed that in a general google search and several options presented. Most led nowhere, but two led those same parts being sold on amazon, or ebay. One led to a chart that had all the applications that fit specific part along with the manufacturers individual part numbers. I had to take precise measurements to make sure, but i found it. It seems odd to me that on a forum for correct craft that this hasn't come up more often. From everything i have found, this was a relatively routine placement in early 70's correct crafts. I will post a picture with the "canisters" for the hopefully clarification. Because i can find almost no info on these motors. Set up, specifications, nothin.

Atomic Dam wrote: I found the part online. There was a cross refrence number to a mercruiser engine model that uses that same impeller. It should be here wednesday. I did look and there is no strainer on this engine. But there are two inline canisters that look to have hoses to other engine components. Most notably the transmission. Does anyone know what those are?

If there are two "canisters", then one is the trans cooler and the other is probably an oil cooler. I said probably because a oil cooler isn't a common item on these small engines/boats. A picture will confirm.

Where did you come up with the number to cross reference to the merc?

John,
Since it's a Jabsco, here's their chart

Its a Jabsco pump Model 17100-0001. Struggling to find anything

Atomic Dam wrote: Okay, so apparently this is an Escort? 351 pcm. How do I find parts for this? when I went to the local boat shop to get an impeller, they gave me a model specif one for this boat, but it certainly is not the correct impeller.

The proper impeller is for the engine and NOT the boat. I think I'd be shopping elsewhere. .

Escort was purchased by PCM about 1977 or 78 so your engine is a Escort and not a PCM. Some parts interchange and others don't.

Okay, so apparently this is an Escort? 351 pcm. How do I find parts for this? when I went to the local boat shop to get an impeller, they gave me a model specif one for this boat, but it certainly is not the correct impeller. Does anyone know anything about this?

John,
Yes, that's the RWP.

Regarding the strainer, you may or may not have up. It's typical location would be between the thru hull water inlet and the trans cooler

Understood. Just picked up impeller to replace. Going to do that now. I was told by the parts guy to check the strainer gasket. Where is that exactly?

The Jonny Quest "how to avoid overheating" credo is:

1. Change raw water impeller every 2 years
2. Change thermostat every 3-4 years
3. Change temperature sending unit every 4-5 years
4. NEVER run engine without water.
5. Watch temperature gauge regularly while boating
6. Inspect risers and clean-out with each year's winterizing

Hopefully, your engine didn't get too hot for too long. Heat can screw-up a lot of things. Be vigilant and check your oil for signs of water intrusion. If water is getting into the oil, look under the oil fill cap for residue that looks like chocolate milk. Also, check the oil regularly to see if the oil looks "milky" and kinda like chocolate milk. That can be signs of a cracked head or head gasket issues. Both can occur with overheating.

JQ