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Mercruiser 37L 470 Questions

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"I've got a co-worker that

"I've got a co-worker that selling his 1989 WellCraft with a Mercruiser 3.7 and alpha-1 drive ($4,000.00).
He is the original owner and known for taking Excellent care of all his toys. The fact that it was his boat got me interested!
He told me that he had to replace the rectifier ~ 2years ago and it cost about $1000.
I was all excited about this boat until I've spent the last 2 hours reading about how the 470 was a disaster/mistake design that mercury eventually bailed on.
Is this engine really a disater?
I'm going to test drive...is there specifics that I should look for?
I'm REALLY interested in this boat, because of the owners rep/history/honesty....but am I buying a headache?
anyhelp??"
 
"[b]"I was all excited abo

""I was all excited about this boat until I've spent the last 2 hours reading about how the 470 was a disaster/mistake design that mercury eventually bailed on.
Is this engine really a disater?
but am I buying a headache? "


Ayuh,.......

Don't Do It............"
 
"modicon2:

"Don't D


"modicon2:

"Don't Do It............"

Bondo hath spoken with straight tongue!

Run like the wind boy and don't look back; something may be gaining on you.
uhoh.gif
"
 
Jeez guys they aren't that

Jeez guys they aren't that bad. It sounds like it was taken care of with proper maintenance and all. Just do the regular tests on it like compression and leak down test on the closed cooling system and a seatrial and it should be good to go. If you have any further doubts take it to a certified marine mechanic and have it inspected. $4000 for that boat sounds like a good deal if it was well taken care of like you say. My set up is a 1982 19' Sunrunner with the same package. The guy had regular maintenance records and the boat spent it's entire life on a lake.

I spent $5200 but it has been well worth it because I haven't had to do anything except regular maintenance to it. It runs like a top and is very fast and uses low GPH as well. 170hp in a light boat is great. I'm not sure how much a 4.3L weighs but I would guess a lot more than the 3.7L for the about the same HP.

Don't be afraid of it!
 
"I am kind of reluctant to chi

"I am kind of reluctant to chime in (since I have no personal experience with the 470/170), but there are lots of guys on this site from time to time who swear by them. (There are also a few that swear AT them.)
Merc must have made thousands of them; they seem to be everywhere.

From what I have heard one of the common problems is overheating. It seems like that is a very common complaint, esepcially when used in salt water.

If you have a good one that has been well maintained, used in fresh water, and the price is right, it may not be a bad move. As PG has said, it is a lighter package than the 4.3 for sure.

Rod"
 
"I have a 1979 Bayliner Admira

"I have a 1979 Bayliner Admiralty 19' cuddy with that same motor. Bought it used about 20 years ago. It had a burned exhaust valve (no lead gas).
Fixed that and have only had to do routine repairs since. The orig rect went out. There is a spare belt groove on the flywheel so I just bought a belt-driven explosion-proof alternator from my local auto electric shop, fabbed a bracket and it works fine. About $125. With only me in the boat will make 46 mph. And not too thirsty either. Depends on condition but,, JW in Dixie"
 
"Thanks for all the comments.

"Thanks for all the comments.
What's the best way to do a leak down test?
This is a nerve racking decision...one guy says run away from it and another guy says good motor.

I know the owner took excellent care of the boat, and it's all in great shape/clean. I guess I'll base my final decision on the test run.

Thanks again."
 
"Just do a standard compressio

"Just do a standard compression check first. If you find anything inconsistent, then do a leak down test to try to identify the problem.
I can send you the leakdown test procedure if you need it later.
For these engines you shud see compression numbers in the 140-150 psig range.
If you get one or more much less than the others it would be suspect.
How many hours on it?

Rod"
 
"modicon2:

Opinions are lik


"modicon2:

Opinions are like noses, everyone picks theirs'. Go w/your gut instinct after the suggested tests. Remember, friends buying from one another can become enemies real quick. If you buy it, don't discuss it for any reason w/your friend. Win or lose, it's your choice.

P.S. New exhaust manifolds are like hens teeth, they don't exist.
uhoh.gif
"
 
"I was thinking more of a pres

"I was thinking more of a pressure leak down test for the cooling system. I've heard of cylinder leakdown tests and they are quite involved but better than a compression test but you should only need one if it fails the compression test to find out more of where the compression is leaking from; head gasket, bad valves or cylinder walls. The cooling system test will tell you a lot of things as well such as head gasket or heat exchanger, I believe exhaust mainifold or bad cam seal and general condition of your cooling system. These problems can cause a lot of expensive troubles as well but it's a fairly easy test while you are doing the compression test. Other simple tests to perform while out on the water is check the temp gauge for stability and where it sits when at normal operation temperature. Mine is only around 145 degrees and I think they keep these engines pretty cool because of the alum block. Also check to see how smooth it accelerates and idles and how quick it starts. Also when the boat is in the water at the launch and the outdrive has been trimmed down check the water around the stern for oily sheen, could indicate a trim cylinder leak. If it passes all these tests I would say you have a pretty sound motor on your hands. Not garanteeing it because after all it is a boat!

But the key word to any boat is regular and proper maintenance and cleaning, especially if used in salt water. If it wasn't properly cared for you will have trouble with any motor."
 
"HI GUYS, I HAVE A 3.7 170HP M

"HI GUYS, I HAVE A 3.7 170HP MERCRUISER WITH LEAKING CAM SEALS. IT IS A SLOW DRIP FROM THE WEEP HOLE.HAS ANYONE OUT THERE EVER TRIED STOP-LEAK OR WATER PUMP SEALER ON THIS PROBLEM ? IF SO, HOW DID IT WORK OUT ?"
 
"Patrick,

I've had that


"Patrick,

I've had that same leak and it is better to replace the seals on the front cover. There are two seals that you need to replace. One keeps water from entering the engine and one that seals the impeller. Need to order the gaskets for the front cover and impeller cover.

Unfortunately, you have to remove the harmonic balance and stator, impeller and cover, then the front cover. I did not have to lift my engine but be careful with the pan gasket. If you break the pan gasket, it is a pain to make a patch, but mine worked fine and no oil leak."
 
Very happy with my 1979 Mercru

Very happy with my 1979 Mercruiser 470. Runs like a top and uses less fuel than most. Look after them and they are a good motor.
 
i have 1979 470 on witch i thi

i have 1979 470 on witch i think the starter went out i removed the starter got it tested and passed but it has the gear or sprocket up should it retract in couple friends told it should parts store guy could'nt tell me
Thank you
 
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