Parts compatibility

[jwr_20]

Hello all.<br /><br />I currently have a 75 HP Merc from 1984 or so. I also have an 850 85 HP from 1976 or 77. The 85 had a compression problem and after tearing it down and assessing the costs, it was a lot cheaper for me to get the 75 I am using now. I am looking to sell all serviceable parts off on ebay or wherever, but before I do, I want to find out what parts I could save for use on my 75. The compression problem was due to broken rings on cylinder 3, which scared the cylinder walls. Besides that, I broke 3 bolts off while taking the powerhead apart. The block is serviceable but needs to be resleeved in #3, and the bolts need to be drilled out and retapped. The connecting rods are in great shape, and three remaining pistons are good, the crankshaft is good, and the carbs were rebuilt back in August and used only once. I guess I am more curious on the lower unit. The 85 lower unit is in perfect condition, and totally serviceable. Would that lower unit be compatible with my 75? The props are the same, and I have already swaped them as mine was in better shape, and I managed to take the trim tab as well. Both lower units look the same from the outside, and they appear to be the same size too.<br /><br />Any ideas would be great. Thanks a lot.

 

[WillyBWright]

Re: Parts compatibility

Having parts motors around is usually a good idea. A lot of parts will work, some might not. The gearcase should, but you might have a different gear ratio. As for what to sell on eBay ... if it don't look like what you have on the 75, go ahead and sell it. Don't even think about overhauling that old block. Yank the good parts and chuck the block.

 

[jimalsk]

Re: Parts compatibility

You may want to take a little time and do some cross referenceing on some of the high ticket items like the carbs, the electrical components. It would be the pitts if your stator went out on the 75 and the one you sold or throughout off the 85 would have worked. Scan your Seloc manual and see if any of the parts cross over.

 

[Kenny Bush]

Re: Parts compatibility

I would keep that motor in the shed for spare parts. The lower leg will swap as well as many other motor parts. If you part it out on Ebay, I think you will spend 10x the money to replace parts new. You could get rid of the cowling and midsection (Keep trim cylinders), but the lower leg and powerhead bolt ons can be used. Shade tree mechanics do better with a bone pile to pick parts from. If you do your own service work, keep that motor for parts......

 

[jwr_20]

Re: Parts compatibility

Thanks a lot for the info. I am going to hold on to anything that will fit my 75, and try to sell the rest. I will also cross reference the parts to determine compatibility as well. All the parts on the 85 are still serviceable except for the the one piston, and the block that is probably worth more as scrap than reservice!<br /><br />Thanks again for the great advice!