Need help with my 3.7l mcm 180

[nola mike]

I knew the drive was seized because when i pulled it out and put it on drive i couldnt turn it

It will be hard to turn in gear... Did you try putting it in neutral?

 

[The Begginer]

It will be hard to turn in gear... Did you try putting it in neutral?

Yes and it turns ok

 

[The Begginer]

Yes and it turns ok

In neutral

 

[The Begginer]

Btw i needed some spark plugs for my engine so i asked around localy and found a NGK BP7HS so i measured it and it was around 10mm longer but the part wich goes in the engine us about 2mm longer is that ok and has anyone here used that spark plug before ??

 

[nola mike]

Yes and it turns ok

Then it probably isn't seized

 

[Eric 3.7LX Alpha 1]

I wouldn't run those. The Mercruiser plug # is 33-97389. It crosses to a NGK-BPR6FS.

Did you drain the gear oil out of the drive yet? If yes, was there any water in it? If it has Mercruiser lube it should be a greenish color. You should probably drain and the split the drive halves next. See if the top half or bottom is seized. So what's the deal with the engine? Is at the machine shop?

 

[nola mike]

See if the top half or bottom is seized. So what's the deal with the engine? Is at the machine shop?

He thought it was seized when he was trying to start it in neutral. I'm not exactly sure of the problem he's having

 

[The Begginer]

I wouldn't run those. The Mercruiser plug # is 33-97389. It crosses to a NGK-BPR6FS.

Did you drain the gear oil out of the drive yet? If yes, was there any water in it? If it has Mercruiser lube it should be a greenish color. You should probably drain and the split the drive halves next. See if the top half or bottom is seized. So what's the deal with the engine? Is at the machine shop?

I think its the top half cus my drive has a dipstick on top and when i pulled it it was all rusted so i think its the upper plus the lower spins freely in neutral

 

[The Begginer]

I wouldn't run those. The Mercruiser plug # is 33-97389. It crosses to a NGK-BPR6FS.

Did you drain the gear oil out of the drive yet? If yes, was there any water in it? If it has Mercruiser lube it should be a greenish color. You should probably drain and the split the drive halves next. See if the top half or bottom is seized. So what's the deal with the engine? Is at the machine shop?

Ohh and how about if i use a external resistor instead then would it be ok??

 

[The Begginer]

Ohh and how about if i use a external resistor instead then would it be ok??

Nvm it doesnt fit

 

[The Begginer]

Hi guys just wandering to know about the common problems of a merc 470 and the fixes thanks

 

[Scott Danforth]

Hi guys just wandering to know about the common problems of a merc 470 and the fixes thanks

just search merc 470 on google. or this site

Google Search

www.google.com

 

[Eric 3.7LX Alpha 1]

Hi guys just wandering to know about the common problems of a merc 470 and the fixes thanks

Maybe you missed it.. I don't know? It's been discussed already. Go back and re- read post 27 and post 29 in this thread.

 

[The Begginer]

So did a bunch of research and found out it’s a 488 not a 470 cus it has a 4brrls carb does that change any problems ??? thanks

 

[nola mike]

So did a bunch of research and found out it’s a 488 not a 470 cus it has a 4brrls carb does that change any problems ??? thanks

No

 

[The Begginer]

Ohh well that sucks but specifically just wondering what are the difference between the two???

 

[Scott Danforth]

Ohh well that sucks but specifically just wondering what are the difference between the two???

the intake manifold and the carb.

exact same motor, except one is a 2-barrel, one is a 4-barrel

other than that, same poorly designed block, same poorly designed water pump, same soft cam nose, same problems

 

[The Begginer]

to expand on above

the 470 has an iron head and aluminum block. the block has an open deck (floating bores) because it was cheaper for mercruiser to build and they didnt spring for the aluminum head. so as much as a 10 degree overheat and the block moves enough to blow the head gasket. the fix for this is a bore spider welded in the block to stabilize the deck and an aftermarket edelbrock aluminum head

the inherent issues with the ford head, valve train and non-adjustable rockers requiring different push rods for any head work, GM style block/cam, GM style timing, GM flywheel and custom mercruiser crank......

the heat exchangers that were originally paired with the engine were too small. this lead to large amounts of overheated engines and blown head gaskets. eventually mercruiser installed a larger heat exchanger

the water pump is driven off the cam snout. the cam snouts were never hardened as that would have cost money. so the seals wear thru the cam snout material. the fix is a speedi sleeve.

the stock charging system was pulled over from the outboard lines to be cheap. the charge output was modest as it was only intended to charge the battery and run lights. not enough output to run radios and other electronics. however the regulator is the week link. since that is no longer being made in high volume, that little water-cooled beauty is about $500. hence the aftermarket external alternator conversion

most of the parts for the 470 are NLA

as to replace it. I would find a complete and running 4.3, preferably with an alpha 1 gen 2 and swap the motors pulley to prop

So if I put an external alternator on it does it mean that I won’t need the regulator anymore?? And if so can you send me a wiring diagram thanks

 

[Eric 3.7LX Alpha 1]

Yes, the voltage regulator will be inside the alternator. I have the wiring diagram at home, will post later.

 

[The Begginer]

Yes, the voltage regulator will be inside the alternator. I have the wiring diagram at home, will post later.

Thanks