1985 Evinrude 30 HP Powerhead Removal

[robm1]

I've been searching all over and can't find powerhead removal procedure for this motor. I understand throttle and shift linkages need disconnected, but where and how? It looks like I should be able to disconnect throttle control rod by removing small wire keeper, remove armature spring, control lever keepers then slide away from motor for clearance. Is there a better way? I don't know if LU needs pulled to disconnect shift linkage from powerhead. Any help would be appreciated.

 

[oldboat1]

A service manual would provide procedures, but a parts manual would also be helpful: https://www.ebay.com/itm/1985-OMC-J...ash=item440f3fcd7c:g:jckAAOSw-5dZ-RHV&vxp=mtr (I didn't see an '85 service manual, but only looked briefly.)

No offense, but it sounds like you might be new to outboards. What is the reason for powerhead removal?

 

[racerone]

You might as well remove the lower unit now.----It will need a new impeller.----Remove the water intake screens to disconnect linkage.

 

[robm1]

Owner had it overheat then left it sitting for years. I got to this point after performing the following: I removed lower unit and replaced lower gear case seals which were leaking, replaced the whole impeller housing, plates, impeller, upper housing extension because it was a melted mess and made sure all debris was removed from water intakes and copper supply tube to powerhead. Removed carburetor, cleaned and adjusted to initial specs. Removed water cover, cleaned all passages with water and compressed air, replaced thermostat, decked head to within .5 thousandths as head was warped and replaced appropriate gaskets. Fired it up and was streaming out tell tale and exhaust fairly well, but still ran hot on upper cylinder. All water deflectors were in place and cylinder walls were in good shape. Compression is good.

 

[racerone]

And what is " good compression "--On this overheated motor ?

 

[boobie]

What do you call hot on upper cylinder ??

 

[robm1]

Compression was 124, 125 upper, lower... temp on upper was trying to get in 190's to 217 before shutdown. Removed powerhead by removing throttle control rod, armature spring and control arm. Removed neutral safety switch control link by removing cotter pin, removed 4 bolts and two nuts retaining powerhead and removed it. Problem was debris had migrated into inlet of powerhead which you cannot see through midsection. With powerhead removed you can remove exhaust housing and clear debris, replace gaskets, reassemble and good to go. Thanks for the help.

 

[oldboat1]

Particularly if you are a river and marsh runner, best to replace the impeller annually and do a thorough flush. Flush up through the water tubes while the lower unit is removed for service, and spray up in the leg to clear out any debris.

Not as easy on your motor, but periodically pull off the cover and the t.stat and flush down.

When storing, cover the lower unit to keep critters from inviting themselves in and setting up housekeeping.

Good luck -- good boating!

 

[robm1]

I appreciate the feedback oldboat1. I agree with you and tell my customers the same. When I spoke of debris, I meant remnants of old melted impeller which had lodged so far up in water passage in exhaust housing you couldn't see it and the new water pump and impeller took a bit of time before it fully closed the passage. Word of advice for anyone changing water pump due to overheat; after repair always check cylinder temps near plugs. Any excess temp or major difference between the two indicates a need to investigate further. If this motor, which ran good after head, water pump, etc. were returned to customer without a temp check, motor would have overheated again. Thanks all!