Taking power head out of Enduro 8hp?

[labougie]

I have a 1992 Yamaha Enduro 8hp, model E8D which is based on the earlier 8B and I’ve been trying to track down the source of an overheating problem. On starting up, the motor pees plenty of water through the tell-tale but after a while under load the flow reduces and heats up until it's pure steam. So far I’ve changed the corroded lower bearing plate beneath the impellor and also flushed the system through with 5% hydrochloric acid for 2 hours which produced masses of crud but neither of these cured the overheating. I thought I’d check the head gasket but taking the head off, the lowermost bolt sheared off in the block so if I can't get the broken stud out with WD40 and Mole grips, I'll have to drill and Helicoil it. There is no 90 degree access to the bolt as the lower cowling is in the way. Will the lower cowling drop down to allow access, or do I have to pull the entire power head off? If so, any advice on doing this, please? Tks in advance.

[TownsendsFJR1300]

Unfortunatly, your issue is probably in the water jackets, salt crusted up(if not flushed with salt water use).

Re removing the bolt. I would pitch that wd40 and use something else eventually(I like PB Blaster, works amazingly well).

**If you have accesss to a small MIG (wire feed) welder, take an appropriate sized nut and WELD IT (PLUG WELD) to the broken stud/bolt.

Obviously cover up anything you need to protect, remove fuel issues and IMO, would disconnect the ECU, battery, anything that could possibly fry.

Once that nut is welded, you can use some penetrating oil IMMEDIATLY(while hot), and put a wrench on it. Even VERY SLIGHT MOVEMENT back and forth is good (add a good penetraring oil), slow and steady. Do NOT force it immediatly.

You may have to weld a nut several times but between that and the heat, usually does the job..

Good luck and please post how it goes..

You don't need much room for a MIG welder tip and most likely WON'T need to remove the powerhead, etc..

[labougie]

Thanks for that - I have a chum with a MIG and I'll try your idea.

If it comes down to it, is it a real PITA to take the power head out? What's involved?

[TownsendsFJR1300]

If it comes down to it, is it a real PITA to take the power head out? What's involved?

Never done one, just what I've read here...

Most were't too hard EXCEPT that you run into bolts breaking (from rust/old age-same as what you have) (depending on the age) so you might be opening a can of worms..

"99yam40" (40 HP) just pulled his power head for the first time (re-built crankshaft), didn't sound too bad..

Someone else while have to chime in if it gets down to it.

[gohar said]

I have a problem of wiring connection on yamaha E8D ENDURO 8 HP outboard so please i need a guide line