Honda 10 hp problems

[Bait O' Eggs]

I currently own a 10 Hp honda long shaft, I am not sure of the year but the serial number is B100L-1400134 (older blue and white model probably mid 80's) I have ran it for 3 or 4 years with no problems. I recently developed a problem with water in the oil. In the process of trying to resolve the problem I have broke off 3 bolts in the head where you access the thermostat. I have destroyed my current head trying to remove the broken bolts. <br /><br />I have found a used head I can purchase for $75 but am not sure I have found the problem where the water leaks into the oil is. I did find a bad gasket on the oil drain plug which may have been the problem. When I pulled the head I did not find any clues that show the water was leaking at that location. <br /><br />I have also found a 10 hp short shaft of what appears to be the same vintage, maybe a little newer serial number B100S-1702682. This motor has no lower end as it went bad and it is taken apart and sitting in a box for a few years. <br /><br />I want to know if it is possible to put my lower end on my long shaft on this short shaft motor and make the short shaft a long shaft. Do the bolts match up on both models????<br /><br />I hate to buy a new head for my current motor and still have the oil/water leak problem on my current motor not resolved. <br /><br />I need to know if this is an option before I buy the short shaft with the bad lower end.<br /><br />Maybe I can steal the head off the short shaft and make my long shaft work (assuming I can find oil/water leak) and have some spare parts like carb, hood, skeg etc.......<br /><br />Thanks for the help.

 

[hondon]

Re: Honda 10 hp problems

Thank you for the well put post. The most common way for these engines to ingest water into the oil is from the outside in. If you have changed the boat you are running this on or the waterway this might be a consideration.Otherwise there are three places you need to concern yourself with .The oil filler neck is likely made of ceramic plastic on this vintage and can become warped after time and certainly after an overheat.You will need to pull the powerhead to replace the neck and o ring seal that goes with it.The head is already off so theres that oring and the P.H. will be off so theres that gasket and oring.Check all those areas for flatness.The local machine shop can likely get those bolt out for you at about 30 bucks a pop so that makes the head sound not too bad.Never hurts to have a parts motor around.

 

[Bait O' Eggs]

Re: Honda 10 hp problems

Hondon - thanks for the information.<br /><br />Last night I purchased the 10 hp short shaft ($250) with the lower end in a box to try and make one motor out of the 2, maybe 2 motors if I get lucky.<br /><br />I noticed right off that the oil filler housing is made of metal not plastic on the new short shaft I picked up. The oil filler housing on my motor is plastic. <br /><br />I spoke to the local honda dealer again yesterday and they are addimant that the water leak is probably due to the thermostat not regulating the water to the right temperature. I have a really hard time buying into that logic as when I start the motor the temp is not up and it would always leak when I first start it.<br /><br />I am quite sure the oil water leak is not between the head and the block as the O ring looked perfect and it is backed up by the gasket and neither show any sign of leakage.<br /><br />I have not pulled the plastic oil filler body and that is a possibility for a leakage yet. <br /><br />I strongly suspect I found water leak when I found the bad plastic gasket on the oil drain plug.<br /><br />What I really need is a diagram of how to assemble the lower unit on these motors. I think I can pull the lower end off my long shaft and assemble it on this short shaft I bought last night and have a working motor in a couple hours. <br /><br />With any luck I can either get my head fixed or pick up a used one and reassemble my motor with the short shaft on the bottom of it and have a second motor. I dont see why the guy thought this lower end was shot. All the bearings turn freely, it all appears to be there, or least the box of parts appears to be full <br /><br />Is there a diagram online for assembling one of these 10 hp honda motors??? Where can I aquire an assembly diagram f not online???? I am underway on a project that I have no idea how to accomplish. A map would really help.<br /><br />thanks again

 

[alcan]

Re: Honda 10 hp problems

Hi Bait<br />My best advice is, go to the honda dealer and order a manual. Since you now have two motors to repair. Good luck, have fun.

 

[steelespike]

Re: Honda 10 hp problems

Try the Manuals tab at top of page.Maybe there is on there. Spike