Okay, I finally got it to idle ( still learning).
I can't get it to accelerate to top speed. Goes 45 kph max at the moment.

I need options of what to look into. Next thing I will check is the belt condition. I read the ignition timing could be a culprit but not sure how to check.

It revs up but not out of control. And when I pin the throttle I don't spin or get the power required to pull the front up.

I thought these were supposed to have pretty good power.
Oh and the oil pump is disconnected on mine along with the override.

 

Like you said,check the belt and clutches.If belt has more than 1 1/2" deflection from the center,it's worn out. Plus check for any burnt/glazed spots on the sides of the belt. If the belt condition is ok,worn ramp buttons,damaged helix itself in the rear clutch can cause loss of power. Even worn guide buttons,worn plain bearings in the front clutch can cause problems.Wouldn't hurt to look at chain and sprockets either,especially the front sprocket for wear/rounded teeth.

 

Would rounded teeth cause the chain to jump? I know that's not happening. Can I dig into the clutches without much mechanical knowledge and in the driveway, any special tools needed?

 

Rounded teeth would cause the chain to jump and you'd normally hear it. On the clutches you do need a front clutch puller or get a 3/4" x 16 pitch thread bolt at a hardware store to pull it,plus you have to have a spider tool to break the front clutch down to replace guide buttons or replace the inner plain bearings if worn. Rear clutch normally just slides off unless it's been on awhile and frozen. Pullers are available for them if needed. Several videos on you tube that can give you an idea what's involved.
Plus I like this old guy when he disassembles a front clutch..
Other options are that you can take clutches into a shop and have them rebuild them if you don't have the time,inclination,tools,etc..

 

Fantastic, that 2nd video shed allot of light on the internals. I understand clutches and kits allot more now.

 

He is pretty cool

 

A worn out belt will kill your power. No telling how old the belt is, more than likely is shot. A 400 Explorer should go at least twice the speed you were getting out of it.

 

Greg74 is right. You should be able to get double that speed and a new belt might be all it needs.

 

Just got a belt from napa $51 would have been 85 at dealer. 34 online. Quite the differences.

 

Well, there's your problem right there sonny there was a crack in the cover, missing some bolts, the gasket is torn and guess what?

The drive clutch only compresses less than half inch. Something must be seized in there. Would this cause the issue. :duh:

The guy I got it from said he just replaced the belt and he did ( it looks good). But I think it needs an overhaul. Can I make a puller with a 3/4 bolt #16 thread?