'93 60hp Rebuild Questions

[HybridMX6]

Re: '93 60hp Rebuild Questions

Thanks for that info, I'll make sure I check that before I pick it up.

 

[mikesea]

Re: '93 60hp Rebuild Questions

You were concerned about pitting.You can have the block decked,OR,you can get a piece of marble ,wrap a piece of 80 grit wet and dry paper and deck it a bit yourself to get the pitting out,BUT,in doing yourself you wont know exactly how much material you took off,a machine shop will often place a stamp of the amt block was decked for future referance.As for the other two cylinders and changing rings.Simply honing does not make the cyl.even.if it is out of round it will polish the out of round.Then putting new even rings will actually cause you more problem then if you re-use the old rings which is not recomennded.At this point,your talking a couple hundred more to do it perfert as can be.I suggest(ive worked for good rebuild powerhead shops and bad)and good shops do this,replace all 3 pistons,which come with the new rings ans wrist pins,bore to the smallest needed size should you or someone down the road choose to rebuild again.Some 3 cyl.engines,why I dont know,have idleing probs after new oversize pistons are installed.It may have to do with carb.TYPE also,but we needed to put smaller air jets in a few of the engines around that yr.Dont panic if it runs bad at idle.if you have trouble I will touch base with a guy who know s more(its been 10 yrs.)Be sure to inspect the exhust cover decks for pitting as well.Thats a great eng.Good luck.Mike

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Thanks for the input. They were going to measure the cylinders and see how back they all are, then either bore or hone as needed. One definately needs boring, the other two he said he wouldn't know until he checks them out. As long as they aren't out of round, and are hone-able, I will most likely go that route and just replace the rings. The two other pistons are relatively newer anyways, they aren't even discolored yet compared to the top one that was bad. There is some carbon on the face of them which I would be removing prior to rebuilding, but other than that they look great. The price differnce between 1 piston and 3 is about $250, so unless those other 2 are bad, I doubt I will do all 3 anyways.
As for the pitting, I already have 2 head gaskets, so I'm going to reseal it as recommended in the manual and see if it's good. If not, I have another one I can use, although if I deck it I will end up needing a thicker gasket, would I not?

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Well, just an update for now. I got the block back from the machine shop yesterday. The top cylinder had to be bored .030" over, the bottom two were within spec and he just honed them. The bottom 2, however, had already been bored at some point to .020" over, but the top was standard. So someone has rebuilt this engine in the past.
Now, my question is this:
I am obviously going to have to get a new piston and rings for the top, but what else should I be replacing on the other two, and what else in the block? I was thinking at least rings for the bottom two, just to be safe, but what about rod bearings, or the crank bearings? Should I replace them as well? Wristpins and bearings/clips also on the other 2? Any suggestions would be appreciated. I've only worked on car engine before and I was rebuilding the entire motor, all 4 cylinders, so it was pretty much replace everything.

 

[mikesea]

Re: '93 60hp Rebuild Questions

Kinda a tough call.heres why.I worked for a so called rebuild shop once .I've been told to reuse rod bearings unless the engine had obvious signs of alot of use.Or if the rod or crank was bad,rust etc.But if the eng.came apart with no real failure,we reused center mainsand top mains on the crank.Bottom crank bering was usually changed because of location of bottom end close to waterline.Also changed the bottom seal.Often the pistons were put back in their same cylWITH SAME RINGS,again unless there was obvious failure.This shop worked on low budget for all including customer.As in your case,your top cyl.had failure.So we would bore and fix that cyl.Of course,if a customer wanted all new.then we bored to next oversize ,new piston kits,new berings all through.Will your eng run OK .re-using what was already in there.Probably.I would like to hear the opinions of others regarding NEW RINGS in unbored holes.Again.The out of round hole (possibly,honing dont straiten holes,only polishes )with new round rings,It could actually hurt you,loss of compression .But.Eng was ovbviously rebuilt.WHY??Bottom 2 prior,now the top.I would dfinatly be sure carbs were ok and Timing.If the engine has minimal hours,new rings on the bottom may not be an issue.If it was me.I'd do all 3 bored,with new piston kits,new bottom main bering,bottom main seal always,new rod berings ,new rod bolts,disassemble carbs,if carbs have any issues ,new kits in carbs.change impeller and gear oil,.you can then know its rebuilt throughout.

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

I'm pretty much planning on doing most of this stuff. I already have the cranks seals, and am planning on getting the crank bearings also. I'll have to inspect the rod bearings and see how they look before deciding on what to do with them. I have also already replaced the entire water pump assembly, housing, impeller, etc., andhave 3 carb kits to rebuild the carbs, I just haven't got to them yet. I'm also repositioning the fuel pump due to someone has already removed the VRO system and I didn't like how they had the fuel pump. It was just laying there (which I have heard is ok), but the fuel line was almost kinked where it came into the motor and went to the fuel pump. I'm buying all new fuel lines for it also, since the old one(s) seem to be remembering their shape, including the kink.

 

[mikesea]

Re: '93 60hp Rebuild Questions

Sent You private message

 

[Randybeall]

Re: '93 60hp Rebuild Questions

I have read through all the posts in this problem and not found out what the cause of the engine failure was. If you don't know that do not restart the engine till you determine what was wrong in the first place. Mechanical forensics is a challange but necessary. Carbs, leaky intake, timing? You need to determine this before enjoying the fruits of your labor.

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Well, my honest guess was overheat. When I pulled the lower unit off this thing I ended up with about 5 pounds of dirt that was caked around the water pump and shift rod. My guess was someone let it sit for a long time in the water, and it got buried in sand. Eventually the sand had managed to work it's way in, and when they ran it all the sand probably blocked all the passageways. It pumped water when I got it, but the water pump housing looked horrible, so I'm thinking they eventually got it cleared out, but it was too late, especially since someone has disconnected and removed the VRO and all alarms, they would not have known it was overheating until it was way too late. I've since replaced the entire water pump, am rebuilding the carbs this weekend (I hope), and have got the block back from the machine shop. It's all cleaned up, no blockages to be found, and I've also checked the tube that goes from the midsection up to the engine, and it's clear. So all I can do for now is rebuild it and go from there. If I have problems I'll have to address them as they come. It's on a stand I made right now in the back yard, so it won't be run without a watchful eye on it, and a finger on the trigger so to speak (keyswitch to shut it off in the event of a problem).

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Well, reviving an oldie (sort of), but I finally paid off some bills and got the remainder of the parts ordered for this thing so I can put it all back together. A batch of the parts came in today, and hopefully the rest will also show up today or tomorrow (they were shipped by different carriers). Hopefully this goes smoothly, but since it was Nov. when I pulled this thing apart, I may end up with some "loose ends." Hopefully not though.

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Ok, here I am, bright 'n early Saturday morning, and I already have questions. I got all my parts back out, separated, cleaned the block completely per the manual, dried it with compressed air, and now I'm on to assembling the pistons.
I have a ring compressor for getting the assembled piston in the hold, but I haven't even got that far yet. The manual calls for a special tool for getting the wristpin clips in, but does not show me a picture of this thing. It called for another one for getting them out, which I actually already had a pair if pliers that worked perfectly for that, but getting them back in doesn't work the same way, at least it hasn't yet. So, before I sit here and ding up new parts, how do you 'ol salts at this get the wristpin clip back in? I've got the needle bearings greased and done with the wristpin in the piston, but the clips are givng me fits.
Guess I'll go clean some other parts or something while I wait for some assistance.
Thanks

And another question I now have:
Since I can't do anything further without knowing how to get the retaining clips in for the wrist pins, I started trying to re-do my LU's shift rod seal. Mine had frozed to the shaft, so I had to cut it off. Now, I have the new one, new seals, and new o-ring that goes in there, but how in the heck do you get an o-ring this large into that hole and then into the groove for it? Can someone also please tell me how to get that thing in there?

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Anybody?

 

[bob johnson]

Re: '93 60hp Rebuild Questions

And another question I now have:
Since I can't do anything further without knowing how to get the retaining clips in for the wrist pins, I started trying to re-do my LU's shift rod seal. Mine had frozed to the shaft, so I had to cut it off. Now, I have the new one, new seals, and new o-ring that goes in there, but how in the heck do you get an o-ring this large into that hole and then into the groove for it? Can someone also please tell me how to get that thing in there?

well I had the same problem...and the shop gave me a huge O-ring that was supposed to fit...seem daunting...so I could see the there was a brass insert in the aluminum...so i truned the housing over and drove the brass peice out....

the id of the brass pieces is where the O ring resides...and when the brass pieces is driven in, there is a gap( for the width of the o-ring.

Ill just insert the o ring before i drive the brass piece back in!!!

but i think a LOT of grease would do the trick if you didnt want to drive the brass piece out.

bob

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Yeah, I had 3of these o-rings, already destroyed one of 'em trying this. How did you get the brass piece out? I was considering that, but don't know how to get it out. I've got a 2nd o-ring wedged in there right now, looks like a 4-way folded donut (I folded it in half, then folded that in half, then crammed it in the hole), but it still aint' goin in there right. At this point the worst case is I take it to a repair shop and pay them to do it for me. I need some misc. oils, sealants, etc. anyways so I can continue getting this thing put back together (like Gel Seal II), so I may make a trip to a shop that has helped me in the past. Single private owner shop who gave me machine shop info to take the motor to, place he uses. I guess we'll see, unless I can figure out how to get the brass piece out.

 

[bob johnson]

Re: '93 60hp Rebuild Questions

well first did you remove the old o-ring yourself and have it in hand?

if so is it the same size as the one you are trying to stuff in there??

if so then good.

with the old o-ring out...you can support that housing upside down and take a drift( straight not tapers) with a flat end and go down inside the hole and catch the edge of the brass bushing and tap it out...you need to tap a little then rotate 60 degrees and tap and then rotate 60 degrees and tap.... you are going around the id of the housing and tapping this brass pieces out straight....if you try from one side for too long..you will bend it and or jam it...you need to work it out straight , thus the going around the perimiter..

make a not of how flush the outer lip is to the aluminum housing....so you can install it to approx the same depth.

good luck

i am sure a lot of guys know a trick to stuffing that o-ring in there....with out dissasembly!!

but this method worked for me

bob

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

Well, the old shift rod seal was literally frozen on the shift rod and I had to cut it off with a dremel, so I don't have the old one on hand. I'll give your method a go when I get a chance and see what happens.
Thanks for the info.

 

[bob johnson]

Re: '93 60hp Rebuild Questions

Well, the old shift rod seal was literally frozen on the shift rod and I had to cut it off with a dremel, so I don't have the old one on hand. I'll give your method a go when I get a chance and see what happens.
Thanks for the info.

well I am having a hard time visualizing that...this o-ring that is so hard to get into its slot by pushing down that small id, actually came out of said slot WHILE ON THE SHIFT ROD!!!

seems almost impossible...


good luck

bob

 

[HybridMX6]

Re: '93 60hp Rebuild Questions

I had to cut the entire shift rod bushing/bracket thing off, not just the o-ring. I had 2 halves after I was done, and had to pay $120 or so for a new one, plus the o-rings. I am surprised the new housing did not come with an o-ring pre-installed, but oh well.