1984 Mercruiser 260 head gasket job, lots of pics and questions!

[FreeBeeTony]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

" The tappets look perfect on both the cup side and the cam follower side. "

Did you remove the lifters?
If so they MUST be put back in the same location or you will ruin your cam....

just my $0.02......

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Be careful with those manifolds. Check the machined faces VERY closely. Check for flatness.. And toss those green gaskets in the trash. Get genuine... Those green gaskets are a disaster waiting to happen. The top gasket set looks ok, just make sure the head gaskets aren't steel... SS is ok or composite...

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Be careful with those manifolds. Check the machined faces VERY closely. Check for flatness.. And toss those green gaskets in the trash. Get genuine... Those green gaskets are a disaster waiting to happen. The top gasket set looks ok, just make sure the head gaskets aren't steel... SS is ok or composite...

Will do. I think im just going to.source all the gaskets from the local marina in for ease.

I checked the lifters one at a time and put them back in the same location and orientation they came from.

I need to replace the fuel level sending unit too, is that a special marine application or just a regular automotive sender?

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Progress made! The engine is 90% back together. Still need to install the ignition and set timing, and replace the temp sender. Then a couple hear cycles and a couple oil changes to flush the water from the block and it should be ready.

I found some pin holes rusted through the original valve covers so I picked up cheap dress up kit. Looks cool, hopefully will last a couple seasons before I have to replace with some marine grade ones. Still need yo install the thermostat housing as well. Hoping to ha e it on the water for testing on the 4th.

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

If you are still looking for a manual -> https://docs.google.com/leaf?id=0B1...ODAxOS00YWZjLWFmZDgtZjMxNjQxOTkzMzUz&hl=en_GB
And for the drive -> https://docs.google.com/open?id=0B1TAvwZ3TjhfOVRUNEk0anBUR3lQYTkwcUh5RElUQQ

Other than that, looking good....

Chris.....

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Awesome, thanks Chris!


Tony

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Another question, I saw the risers seemed to have both a steel gasket and a fiber gasket when I took them apart. Is the steel gasket supposed to be reinstalled with the new fiber gasket?

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Post a picture of the steel gasket...

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Here is the steel gasket.

We got it all back together and it fired right up on the muffs. Ran it for 5 min with engine flush in it, changed the oil and filter and ran it again for about 10 min. Both manifolds stayed cool to the touch, the port riser stayed cool, but the starboard riser got warm. The temp gauge never went above the half mark. Is this something to worry about?

It seemed to be running good so I took it down to the lake and put it in the water, and it wouldn't start...pulled the distributor off and found this:

I found a bunch of replacement ignition sensor kits on ebay, is this what I need?

http://www.ebay.com/itm/Ignition-Se..._Accessories_Gear&hash=item4163a56c96&vxp=mtr

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

That's the right sensor (the ebay one).... Uneven cooling of the elbows is quite normal... That will even out once you have the engine under load and a bit more water flowing through....

That steel plate doesn't need to be between the elbows and the manifolds... As long as you used the Merc gasket (not aftermarket) with 2 slots and 2 small air bleed holes...

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Great, thanks! Yeah used Merc gaskets, so should be good. Glad the riser temp isn't an issue. I'm taking Friday off work, and going to try and find that sensor at one of the local marinas tomorrow.

Is there a writeup on replacing that sensor? Does the distributor need to come out?

If all goes well I should be back on the water for the fireworks on the lake (their doing it on the 7th)! Thanks for all the help!

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

2 screws, 3 wires, no the dissy doesn't have to come out... But you will need to adjust the timing when it's done...

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Perfect. I have a dial back light so once the sensor is swapped out i'll set it at 8 btdc and it should be good.

With the TB-IV I don't need to worry about setting advance timing right? The control box automatically adds the 24-26? needed I believe?

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

Just set the timing at 8 BTDC at 700rpm.... nothing more to do...

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

well, installed the new ignition sensor and the engine fired right up. Set timing at 8* BTDC and it idled perfectly on the muffs. Took it down to the lake and it seemed to be ok, until I idled out the channel to the lake and it was at 3/4 on the temp gauge.

So it won't over heat on the muffs but it does in the water. Tells me the impeller is toast, right? the pressure from the hose pushes enough cold water to keep the engine cool, but sitting in the lake the junk impeller can't push enough water to cool the engine.

I'm replacing the impeller tomorrow, really hope this is the last of the issues...

 

[achris]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

While you have the drive off and apart, check the water pocket cover... Easy to check and real easy to overlook.. and can lead to many an overheat...

This is a post I did a while back to a guy who didn't know what that was... I explain it, how it can come to leak, and the ramifications...

http://forums.iboats.com/showthread.php?t=556903&p=3825409&viewfull=1#post3825409

Chris......

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

I'll take a look when I pull it apart today.

Am I right in thinking its the impeller since it doesn't overheat on the muffs?

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

ok, installed new impeller kit including the housing and water tube. Put it all back together and no more overheating.

New problem now...as soon as I try to shift into reverse the engine dies. It seems like some kind of kill switch? Is there something in the lower unit that I could have missed that would cause it to just die when shifted from neutral?

 

[akorcovelos]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

update, I put it on muffs and it will idle perfectly in neutral, and shifts into forward fine, prop spins. Try to shift into reverse and it kills the engine before the reverse gear engages.

 

[Josh P]

Re: 1984 Mercruiser 260 head gasket job, lots of pics and questions!

sounds like you need a new lower shift cable.. its sticking and tripping the shift interupt switch