Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

[Goat1314]

Hello all

I'm running a 1989 Mercruiser GM 4.3L V6 262 2 bbl

SO My engine over heated and now I have two wet plugs on pistons 1 and 3. I am praying the heads are OK becasue they are cast Iron but I will guage them anyway. I havent' done a job like this sinse high school and the last head gasket I did was on a over head cam so i have a few questions about lifters and push rods.

1. Do I have to remove the rockers and push rods to get the head off and work on the gasket? Or can just slide the head carefully off. If I remember corectly the rockers just sit on the pushrods they are not attached to them?

2. If I take the rockers off do I have to reajust them or can they just be torqued down. I have the book and it's a little confusing. There is a section on how to adjust the rockers but its seperate form the head remouval and instalation so I'm not sure if the adjustment has to be done everytime I take the heads off or not? My lsat V6 with lifters and rods was 20+ years ago i'm a little fuzzy!

I'm prety sure it's only the head gaskets because the engine ran great all morning at high RPM. My Impelar was baked so whenI started trolling at low RPM I ran out of water and cooked.

Any wisdom or help you can give me woudl be greatly apreciated

 

[PowerAddict]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

You do have to take the rockers loose and pull the push rods out, no way around it But its not that big of a deal.

When you go to tighten the rockers again (I don't remember exactly) but its something like; you put it on 1 TDC compression and do half of them to where you can't turn the push-rod through yoru fingers plus like 1.5 turns, then put it at like #5 tdc compression and do the same thing. Pretty easy.

 

[Goat1314]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

You do have to take the rockers loose and pull the push rods out, no way around it But its not that big of a deal.

When you go to tighten the rockers again (I don't remember exactly) but you put it on 1 TDC compression and do half of them to where you can't turn the push-rod through yoru fingers plus like 1.5 turns, then put it at like #5 tdc compression and do the same thing. Pretty easy.

Yeah... That means i have to torque the heads down then re-instal the intake manifold and the ditributor before I re- instal the rockers or I will loose my timing right?

 

[PowerAddict]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

You will torque the heads, and install the manifold before you do the rockers. If you want to mark the distributor and such when you pull it out, you're right, you'll have to stab it before you do the rocker arms.

 

[Goat1314]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

You will torque the heads, and install the manifold before you do the rockers. If you want to mark the distributor and such when you pull it out, you're right, you'll have to stab it before you do the rocker arms.

ONe more question.

Once i open the motor up and blow out all the Oil /water milk shake, check all the pushrods to make sure they are straight clean up the heads and check to make sure they are not warped, repace all the gaskets put it all back together re-instal my distributor then re-adjust my rockers is that it? IF I run it and change the OIl and filter a couple of times will I get the rest of the milk shake out or do I have to tare the whole engine down to the very bones and make sure I get every last drop out?

 

[aerobat]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

IF I run it and change the OIl and filter a couple of times will I get the rest of the milk shake out or do I have to tare the whole engine down to the very bones and make sure I get every last drop out?

no problem, just run the boat for a longer time so it gets warmed up fully and the engine will boil out the water by itself.

 

[NHGuy]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

I agree with what has been said. Also I would check head and deck flatness while apart. When the head is back on set your rockers to get correct lifter operation.
And it's not essential, but I am so anal that I'd set the motor to TDC on #1 before disassembling. Then it's a little easier to position the distributor upon reassembly. You can mark the distributor housing to manifold relation and use that as a rough start point when assembling. With piston #1 at TDC compression, aim the rotor at the #1 contact in the distributor cap.
Then start her up and set timing with a light.

 

[81 Checkmate]

Re: Head Gasket replacement on a 1989 4.3L 262 mercruiser V6

I also agree with NHGuy.......Have the heads cleaned, magnifluxed for cracks and decked by a machine shop. I had mine done $105.00 for both.
Well worth it for the sanity knowing they are good.

Also go with Felpro gasket set.

Just asking.... did you happen to pressure check the cooling system to be sure its a head gasket blown. It could be your riser gaskets...Bondo would be the V-6 Expert!

 

[devintripp]

I have a 1986 OMC 4.3L V6 Mercruiser engine in my Galaxie boat. Firstly I don't know how to look for parts for this so that would be a big help in general.

What is the head gasket set I should buy that will fit that engine?

 

[Lou C]

Fel Pro makes a nice head gasket set for the 4.3 with Marine head gaskets & intake gaskets, it also comes with new valve cover gaskets & one for the distributor.
11 year old thread!!!

 

[devintripp]

Fel Pro makes a nice head gasket set for the 4.3 with Marine head gaskets & intake gaskets, it also comes with new valve cover gaskets & one for the distributor.
11 year old thread!!!

Do you know if this engine has an oil cooler? Or why chocolate milk would come out of the exhaust (there is two tubes that go to the filter flamer arrestor and chocolate milk came out of those when reving it after running at idle for a while.)

 

[Scott Danforth]

Do you know if this engine has an oil cooler? Or why chocolate milk would come out of the exhaust (there is two tubes that go to the filter flamer arrestor and chocolate milk came out of those when reving it after running at idle for a while.)

read the rules

 

[aspeck]

Do you know if this engine has an oil cooler? Or why chocolate milk would come out of the exhaust (there is two tubes that go to the filter flamer arrestor and chocolate milk came out of those when reving it after running at idle for a while.)

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