Mercruiser 3.7 Head Gasket Replacement

[Old Yeller Boater]

Re: Mercruiser 3.7 Head Gasket Replacement

Thanks Terry. For some reason I was thinking this was a 140 thermostat. The temp held pretty well around 140 unless I pressed the engine some. Certainly the gauge variation could be, but had assumed it was pretty spot-on when thinking it was 140.

 

[stonyloam]

Re: Mercruiser 3.7 Head Gasket Replacement

Should be a 160 Merc. pn 99155T2, guess it is not beyond the realm of possibility that someone sold you a 140. If it is running OK probably would not hurt anything if they did. Glad you got the old gal running.

 

[Old Yeller Boater]

Re: Mercruiser 3.7 Head Gasket Replacement

I'm 99 44/100 % sure that's the part number and what I ordered. Not sure why I was thinking 140. The motor is running well though. Now that I have the gauge working, I feel much better about being able to monitor it so I don't have future problems. Next step is carb help to get it starting better. It cranks very slow, takes a LOT of gas (kind of like older cars that you have to give extra gas like it's flooded), and I get a good bit of backfiring if I throttle up too quick. I was going to check the timing last night and also take the distributor pic that Don had suggested in another thread, but it was raining and I didn't want to uncover it. I'm just particular about not getting the interior wet.

 

[stonyloam]

Re: Mercruiser 3.7 Head Gasket Replacement

Might be time for a new starter. Check e-bay for "470 starter".

 

[Old Yeller Boater]

Re: Mercruiser 3.7 Head Gasket Replacement

already on order and expected by Thursday. I am pretty sure the starter is on it's way out. I've turned the key a few times and nothing happens, but turn again and it picks up. Had that happen on a previous boat, so for peace of mind, I'm replacing it.

It's possible that it dragging is part of the problems with the slow starting, but the carb backfires quite a bit, so I'm thinking it needs attention regardless.

 

[Old Yeller Boater]

Re: Mercruiser 3.7 Head Gasket Replacement

starter replaced. Replaced battery too. Also adjusted timing. It seems to be starting and running much better. Lake test to follow.

 

[DBEE]

Can anyone answer which direction the head gasket on a Mercruiser 470 3.7l goes on? The gasket set we received did not come marked top or front. The gasket has different size coolant passage holes on one end so it is definitely asymetrical and directional. Thank you in advance

 

[GA_Boater]

Can anyone answer which direction the head gasket on a Mercruiser 470 3.7l goes on? The gasket set we received did not come marked top or front. The gasket has different size coolant passage holes on one end so it is definitely asymetrical and directional. Thank you in advance

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