I have a 95 explorer 400, and I can't figure out how to remove the four bolts holding the cylinder to the lower end of the engine. I have to top cover off, but I can't get anything except an open end wrench on the lower four bolts, and I haven't been able to break them loose yet. Is there a trick to it, or do I just keep going the way I am?

Also, I'm guessing that the lower gasket is blown. The top gasket looked fine, except some of the rubber was loose around the bolt holes, but the metal was all intact. That made me wonder if I may be looking in the wrong place. There is coolant in the oil line that comes out of the rear of the block and into the reed cage. There isn't any coolant in the oil reservior or in the line that runs into the block on the front of the engine. Is there anything else that could cause this? The quad was running like crap, or not at all when I decided to tear it apart. The piston looks perfect, and the sleeve in the cylinder looks great too. I'd really appreciate any help.

 

ive never been able to find a socket to fit on the lower four bolts.

I broke mine free with an open end wrench like you described with 2 feet of pipe on the end.

or you can try shocking the wrench gently with a hammer.

lube it up first.

sounds like the inner waterpump seal went out and allowed water to get into the oil injection pump. theres a rubber seal and a gasket to keep water out of the counter balancer oil (check this oil), the rubber doughnut style seal goes on the water pump shaft whihc drive the oil injection pump.

this is another reason I would get a block off for the oil injection.

 

Motion Pro makes a wrench that works on the cylinder base nuts, 14mm 12pt.

 

So what do I need to do to check the water pump? Do I need to pull the lower bolts off or not to get to it? Also, are those gaskets included in the tusk upper gasket set or are they seperate? I haven't been able to get a book for this since I'm out in the boonies and pretty much broke right now.

Also, how do I check the counter balance oil? And if I just block off the oil injection pump will I need to replace the gasket still? Thanks for the help conig.

I'll check out that wrench too. Is it the torque wrench adapter?

 

Yes it's the torque wrench adapter....

 

I would suggest a 6 point boxed wrench to break it free. Odds are more of a favor of rounding it off loosen it than tighten it.

 

You may want to try a good size punch with a flat face to it. Place it against a flat on the nut and give it 1-2 good sharp cracks. Dont go overboard, but this shud work.

 

Ok, thanks for the tips. I'll try them out tomorrow and see what works.

Conig- how could I tell if the waterpump seals are bad? And which one would it be? The diagram shows 2, both called oil seals. Or do you mean the gasket? Would they be visably bad or do I just have to replace them both? Sorry for the questions, I'm just not sure where the oil passage is exatly and how it all ties together, and I haven't torn it apart yet. Thanks

 

if you remove the waterpump to check the gaskets you most likely will have to replace it. Its the construction paper type gasket and will most likely break up when pulling the water pump. as will the gasket for the case itself (paper).

you will most likely need 5,6,11 ain this diagram http://www.partsland.com/index.cgi?N...00L-WATER-PUMP

It would be best to replace them all. when the waterpump is removed lightly sand down any rust that is on the shaft over time they start to rust and that tends to cause the leaking.

If you don't have water in the counterbalancer oil then that gasket is fine(until you remove it) after that it will have to be replaced.

 

can I just check the counterbalancer oil, and if its clean not worry about the seals? And do I have to pull the magneto case/crankcase to get at the waterpump?