Trojan Boat Forum

I need a little insight!

I have a great '73 F36. It's in the water after six months of restoration work. Now I find that the starbaord engine runs warm 180-200. Port engine idles as 160. I have checked the interal water pump on the engine. the raw water pump (Sherwood G7B) flow, replaced the coolant, blown out the hoses. cleaned out one return fitting in the exhaust manifold, installed new raw water filter and plumbing but its still runs to warm. I even replaced and then removed the thermostat to see if it was sticking. Nothing so far has helped. The heat exchanger sees to flow water OK as does the raw water pump but how do I check to see if these are working correctly?

I've run a hose pressure water through the heat exchanger and it seems to be clear!

Water flows out the exhaust but not in a big solid stream!

I suspect that it's the raw water pump not delivering enough pressure or I have a blockage in the system somewhere. However the interior of the cooling systems looks great. The brass pump impellor in the 440 looked like a brand new item.

How much water should be flowing out the exhaust?

I've run the pump out onto the rear deck to test it. Its pushes water alright but not like firehose!

Do the rubber impellors go soft in these Sherwood G7D pumps and loose pressure even when the visually looks OK?


Any suggestions?

Thanks for your time


Capt' Fethers'

If you have not launched it yet one easy thing to check is on the bottom of the boat. Mine has metal strainers with holes in them over the water pickups. They had become partially plugged from repeated painting of the bottom. I took a drill bit slightly larger and cleaned out all holes.

Thanks
I have "sort of" thought about that and can't remember looking them over when I'd finished doing the bottom last Decemeber. I'll put it on the list and no doubt it will need to be looked at.

Thanks
David

I had a overheating problem on my 318 it was fresh water cooled the problem was rust forming in the elbows and restricking the water flow out the exhaust also checked trans cooler it had a lot of dirt in it (problem fixed)
Ed

Thanks
All input is most welcome. I already found two gunked up connectors(now cleaned out) where the water flow re-enters the rear of the manifolds but that has not solved this issue.

David

Thanks for the input as it finally encouraged me to haul the boat back out of the H20 and have a look. Sure enough, the thru-hull was blocked not by paint but a large PLASTIC BAG. The boat had only been in the water 5 minutes before it suck it up, covering the strainer grille. Now she idles at 160 for an hour and I have replaced all the hoses from top to tail and know how it all works. I now realize that I could have simply don'd a wetsuit and spent five minutes in the water and found and fixed the problem-Ah next time!!!!
So, it's really a lemon into lemonade and now we can actully go boating. . .

Cheers
Capt' Fethers'