85 Mercruiser 5.7L "clunks" when trying to start

[slshoe2002]

I had a weird thing happen to me last week while on the lake. I took my boat out and it was running fine. first time on the lake this year. new oil new lower unit oil. new spark plugs and wires. so the kids and I were fishing and I was starting and stopping the boat frequently to drift and fish. when I went to start it when we were leaving it just made a "clunking" sound for lack of better description. When it would clunk the steering wheel turned all the way to the right like something was binding. I put it in nuetral and forward and reverse and tried starting a few more times. But I just got "clunk and the steering wheel turning sharply to the right. I rowed thge 22ft cuddy off the lake... No easy task BTW. When I got it home I dropped it in reverse and put it reverse neutral and back and forth about a dozen times and it started right up. I thought I better change the impeller and gaskets, and was hoping taking the lower portion of the engine off would reveal something, but everything looked good. There were a few shavings on my Magnetic plug when removing the lower unit oil... maybe a few more than normal. Anybody have any ideas what could cause this?

 

[tank1949]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

when last time greased gimbal bearings or u-joints? These are kinda like CVA joints closed up by a boot that can and will go bad and leak water. U-joint should be greased every year. Yea, I know this means pulling boat and pulling out drive off housing, but you HAD BETTER DO IT YEARLY!

 

[slshoe2002]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

Thats a great idea. I didnt even think about it. I pulled the lower unit off up to the bell housing and sure enough. there was water in it, and rust! now to find the right parts. I might as well do the impeller while i'm at it.

 

[slshoe2002]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

so my next question is, How do I know what parts to get? Im trying to figure out what lower unit I have. My boat is an 85 Crestliner, so I assume the motor is an 85 5.7. The lower unit has all the correct characteristics of the M,Mr - Alpha I model but my serial number isnt anything like what it looks like when trying to find parts. The only serial number I can find is on the Gimbal ring and the and the upper drive shaft housing... They both match .... A426418... The part im looking for are ujoints... wanted to get the ones from Napa if I could so I can start working on it right away, I have a Napa a mile from the house and is open later than the boat shop. Im also looking for Gimbal bearing, and impeller repair kit and any necessary gaskets I will need. like the one that goes to the bell housing. any help would be appreciated.

 

[sptjet90Reflexx]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

when was the last time you had the shift cable replaced? if your removing the drive should just do the works, new bellows, ujoints (if they are rusted like you say), lower shift cable and check that gimbal for any signs of slack.


---edit .. we posted near same time did not see your 2nd reply.

 

[sptjet90Reflexx]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

take a picture of the drive, we can tell you which outdrive you have.

 

[Watermann]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

Remove one of the ujoints and take it to NAPA, it should have a part number on it they can cross match a replacement for. Don't forget to order some gimbal bearing grease too when you get the parts.

The serial number you gave matches up perfectly at marineengine.com.

GIMBAL HOUSING SQUARE/SPLINED UPPER SWIVEL SHAFT FOR MERCRUISER (R/MR ALPHA ONE STERNDRIVE) ENGINE

I guess there are 2 different models square/square upper swivel shaft and the above link to the square/splined.

 

[slshoe2002]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

So to replace the gimbal bearing it looks like I will need numbers 9,10 and 11 referencing the diagram in the link above. Which is the seal the bearing and the ring. Is there anything else I will need, besides grease I mean. I just want to make sure I dont miss anything, any specialty tools?

 

[tank1949]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

GOT THAT RIGHT!!!! and, shift boot. Sounds like Alpha 1. Alpha 1 Gen II came early 90s. I think. They have external outdrive resevor. You have a weekend cut out for you. Sloshoe will also need alingnment tool to be sure that heavily worn bearing hasn't messed up coupler. Good luck!

 

[Watermann]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

Do you have a repair manual for your mercruiser?

 

[slshoe2002]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

Yes but it doesnt describe the process very well.

 

[Bondo]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

So to replace the gimbal bearing it looks like I will need numbers 9,10 and 11 referencing the diagram in the link above. Which is the seal the bearing and the ring. Is there anything else I will need, besides grease I mean. I just want to make sure I dont miss anything, any specialty tools?

Ayuh,.... #9 is just a seal, you can use it or not,....

#11, comes on the complete #10,...

You'll need a puller to yank the old bearin', 'n a driver to install the new 1, then an alignment bar to check the alignment,...

 

[slshoe2002]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

So I was able to replace the Gimbal bearing in the boat. seated it, checked alignment all looked good. Went to install the outdrive again and the last 2 inches it wouldnt go in, I checked the splines going into the motor and all looked good. tapped it a couple times with a mallet and it went in another inch and stopped. Now it will not go in or come off at all. tried prying it with a pry bar, tried shaking it pulling it, it will not come off. manually rotated the engine, and it rotates fone. Doesnt look to be stuck or kinked in anyway. Has anybody heard of this or know what would cause this? all I can think is the Ujoints are in in a way that is causing it to hook on the Bell housing? but I figured rotating the motor a few times would get them to twist. but nothing will break this free. Any suggestion?

 

[Bondo]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

So I was able to replace the Gimbal bearing in the boat. seated it, checked alignment all looked good. Went to install the outdrive again and the last 2 inches it wouldnt go in, I checked the splines going into the motor and all looked good. tapped it a couple times with a mallet and it went in another inch and stopped. Now it will not go in or come off at all. tried prying it with a pry bar, tried shaking it pulling it, it will not come off. manually rotated the engine, and it rotates fone. Doesnt look to be stuck or kinked in anyway. Has anybody heard of this or know what would cause this? all I can think is the Ujoints are in in a way that is causing it to hook on the Bell housing? but I figured rotating the motor a few times would get them to twist. but nothing will break this free. Any suggestion?

Ayuh,... Hook the trim rams back up, 'n use 'em to push the drive off,...

Then recheck the alignment, 'n be sure ya had things lined up, 'n Everything in Forward Gear,...

 

[tank1949]

Re: 85 Mercruiser 5.7L "clunks" when trying to start

Ayuh,... Hook the trim rams back up, 'n use 'em to push the drive off,...

Then recheck the alignment, 'n be sure ya had things lined up, 'n Everything in Forward Gear,...

But before you go any further, inspect behind shift cabel bellows for leagage and as other have suggested, replacing shift cable my not be a bad idea. You have two key ways, male and femal that must line up on OD and housing. These are for shifter. . I believe that you have to put motor in fwd gear. Now, this is where fun comes in. Drive is heavy and sitting skag on 5 gal bucket (inverted) will take a lot of strain of you and your budy as you move shaft into bearing. You need buddy!!! You have figured out that the male splines and coupler femal teeth don't always line up. Now, make sure BIG o ring is placed inside housing and be careful as you push drive shaft into housing not to dislodge BIG o ring. You also will need budy to look underneath to make sure keyways line up. Make sure water passage o ring doesn't move. There ya have it. Good luck. You need to perform this yearly.