79 115 Merc, 5th cylinder at 30

[rickdb1boat]

You can go to the site below and using the serial number, pull up diagrams...

http://www.mercruiserparts.com/selectModels3.asp?type_id=MERC

 

[tashasdaddy]

Re: 79 115 Merc, 5th cylinder at 30

best bet is to part it out and use funds for replacement. or find a donor powerhead. and rebuild.

 

[emckelvy]

Re: 79 115 Merc, 5th cylinder at 30

How did you determine the block was cracked? That's a very unusual problem for an Inline Merc 6 and even if there was a crack it likely wouldn't result in 30 psi compression in one cyl.

The most likely cause of the low compression in #5 is bad rings/scored cylinder which will be evident if you pull the powerhead and tear down for inspection.

Barring any other damage you can bore that cyl as necessary, install new piston, rings, bearings, seals, gaskets,etc, and be on your way.

HTH and G'luck........ed

 

[RacerChris K]

Re: 79 115 Merc, 5th cylinder at 30


I've got water in the fifth cyl.,due to the plug being milky white, any ideas?

 

[RacerChris K]

Re: 79 115 Merc, 5th cylinder at 30


I've got water in the fifth cyl.,due to the plug being milky white, any ideas?

 

[Clams Canino]

Re: 79 115 Merc, 5th cylinder at 30

Exhaust divder plate(s) leaking. A cracked block is VERY rare in these. And they don; thave a head gasket to blow.

-W

 

[RacerChris K]

Re: 79 115 Merc, 5th cylinder at 30

I'll pull it apart and check, thanks man!