1990 90hp quickstart?

[emdsapmgr]

Re: 1990 90hp quickstart?

It is a little hard to see the head gasket seal ring completely, but it looks intact. If so, that may not be the reason for water in that cylinder. Any chance you have a water leak in the exhaust chest?

 

[drmagnum]

Re: 1990 90hp quickstart?

Craig-this picture was before I cleaned it and at night so the flash kind of made it hard to see. I will take more pics once I get the power head on the bench.

emdsapmgr- I will inspect the exhaust chest. What do I look for?
about a two weeks ago I took all the fuel out of the tank and have been running fresh 50:1 mixed. The oiler has been disabled. when I bought the boat the previous owner said he didnt trust the vro and allways mixed the fuel.
It didnt help that they had disconected the alarm under the instument panel.
I connected it back up and got it working to hear if I am overheating and other problems. I have the oil tank out of the boat right now and have cleaned it out too. I might hook it back up for the restart. the manual gives instruction on how to tell if it is working and to mix during the breakin period.

About two weeks ago or more I tried the oiler and had to completely tear down the carbs after because of black stuff that had coated the entire insides of the carbs. I think it was broke down rubber. the engine may have gotten water in it then from the oiler. It barely ran that day.

So i will inspect the exhaust chest real careful.

I will try to load pictures the whole time if I remember. I sometimes get real focused once I have the engine apart. Like making sure the connecting rod cap is aligned perfectly and lubing everything and checking for play in the bearings and journals.

 

[Craig-]

Re: 1990 90hp quickstart?

Tough to see much in that photo but lower deflector is in wrong location so someone opened it up before you did.

 

[drmagnum]

Re: 1990 90hp quickstart?

I tried to take more pictures but they dont really show much.(blurry and lighting not very good)

wow Craig something else different.
I have never heard of a deflector so I got my parts list out and they list 4 water deflectors. Are they all the same size(about 1.5 inches)? and do they go at 7:00 oclock and 11:00 oclock in relation to the bottom cylinder straight in?

(can of worms) I really did not like what I saw when I looked closer. the bottom of the block is broken. there is a crack where I think the bottom deflector goes and another crack on the right. I have some braze rods and I will practice on one of my old motorcycle parts. I haven't braze welded since high school but I think I can repair it.

 

[drmagnum]

Re: 1990 90hp quickstart?

Please excuse the pictures I don't have a very good camera.

this shows the cracks I think

 

[Craig-]

Re: 1990 90hp quickstart?

At this point you may want to try returning the motor and get your money back. Repairing a cracked block is a loosing battle, if it got hot enough to crack, that's not the only damage sorry to say.

 

[Craig-]

Re: 1990 90hp quickstart?

Looked again at the new pics. How far back do the cracks go?

They might be a result of someone doing something stupid and not heat.

The cylinder is not looking real good from what I can see, so expect more problems like a galled piston.

 

[drmagnum]

Re: 1990 90hp quickstart?

the cracks only go back about 3/4 of an inch. It looks like the work of ice to me. I am learning more and more about boat motors and they are not cooled with antifreeze. seems all the water has to be gotten out and I think someone did not get it all out.

Returning this is not an option at this point.

Got the whole thing boat motor and trailer for dirt cheap(900 bucks) Boat is in real good shape with only fine cracks in the gel coat(I sealed them) next to the ends of the transom real solid though and I really put some force on it to make sure it wasnt rotted inside. hull not all scratched up looks good. Everything is solid on the boat only some minor cosmetics like stained vinyl.
Its a 16 foot sunbird fish and sport. It has water ski tow package the trailer is a fine full tilt trailer with 6 sets of rollers.
most motors this size are over a 1000 bucks in our local classifieds.
As I said before I have repaired, rebuilt and fixed many other vehicles. just not a boat motor before.

I have repaired worse cracks(one in a transmission) with JB WELD. I am considering this option. Being part of the outer water jacket I dont even think this gets that hot.
If the water deflectors(maybe silicone-500 degrees) can withstand the heat in these then I think the JB WELD repair would hold up.

Can you not put your hand on the engine while it is at running temp just after it was turned off?

If not braze welding holds up to a lot higher temperatures and forms a nice non corrosive metal that lasts. As long as this block is aluminum it will seal it and weld it tight.

I will take pictures of the repair as I do it.

(can of worms) I will look for the piston problems you mentioned.
I am sure the problems I find wont end there either.
(keeping my fingers crossed)

I am up to the challenge.

Oh is it OK to apply a little heat to the fly wheel to get it off or will something fry under it?

Thankyou for all your help

 

[jgriner]

Re: 1990 90hp quickstart?

Oh is it OK to apply a little heat to the fly wheel to get it off or will something fry under it?

Thankyou for all your help

read this thread about removing flywheel.
http://forums.iboats.com/showthread.php?t=429507&highlight=flywheel

 

[drmagnum]

Re: 1990 90hp quickstart?

Thanks for the flywheel thread.

I used a cheap steering wheel puller and a 3 foot one inch pipe.
I tightened down the puller with 3, 3 inch bolts the put the pipe under the fly wheel next to the starter applied a little pressure up and gave the opposite side a whack with a rubber hammer and it popped right off.

All took about 2 hours to get power head off and to a bench. including removing all the bolts to get the piston out. Not a pretty Piston. I have seen worse in my Skidoo, but it is still running and this makes 11 years. So I am going to give it a try.

tried to braze weld a couple of old motorcycle parts and good thing I did not try to fix these cracks this way. I will JB Weld them and if that doesn't hold up to what heat is there I will use muffler epoxy. I think as long as I clean the area real well and coat it 1/8th inch thick JB WELD on both the inside and the outside, it will hold. The stuff is not a cure all but I have repaired hydraulic pistons that have held well and didn,t leak. I also repaired a transmission case crack with no leaks. I also repaired an old ford oil pan leak. As long as it doesn't get too hot it will hold up great.

camera ran out of battery. I will put some new ones in it tomorrow and snap some shots.

I still don't know if I want to open the other two cylinders thinking if it aint broke don't fix it.

I honed for about 2 hours and the walls look and feel real smooth.

when I took the old rings off the ugly piston, the second ring was stuck real bad. I cleaned out the grooves with the old rings and gapped and installed the new ones. They were a little over sized so I used the mini hand grinder to take a little off till the gaps looked right with feeler gages.

Its late but my plans for tomorrow have been cancled to I will have a crack at it then. no pun intended.

 

[Craig-]

Re: 1990 90hp quickstart?

T

I honed for about 2 hours and the walls look and feel real smooth.

Check for round, I believe the tolerance is 3 thousandths, but check me on that. If they are out of round any more, rings wont seat properly.

 

[drmagnum]

Re: 1990 90hp quickstart?

The cylinder I honed is less than 1 thousands out of round. not too bad

I am having trouble getting the connecting rod cap to line back up. I am about 1 thousand off. I might be a little less than 1 thousand but does it have to be perfect or will it tear it self apart? I am going to work harder at getting it closer.
Maybe there is a trick to holding them while I tighten them?

I decided to explore a little and took the exhaust covers off. It appears they have been leaking for some time. That seems to me it would have contributed to my idle problems and fuel problems.(low or even opposite crank case vacuum or pressure) I cleaned this plate and cover up and sealed them.

I also took the other cylinder bank heads off. they are also full of what looks to be fine white salty sand. At least those cylinders are smooth in the bores and the head gasket looked brand new. So I cleaned things up and bolted right back together.

I JB Welded the block. It looks great.

I will load pics in the morning. I still have a half a billion bolts to turn on this thing. If I get crackin I can have it in the water next weekend

 

[drmagnum]

Re: 1990 90hp quickstart?

again sorry I do not have a better camera.

the ugly piston

the exhaust plate-the white deposits are where it was leaking

the block repair-keeping my fingers crossed that it will hold up

back to work getting that connecting rod cap lined up smooth with the rod. I am going to try a coulpe of pieces of wood and a c-clamp

 

[drmagnum]

Re: 1990 90hp quickstart?

It turned out that all I had to do to get the connecting rod cap to line up was switch the bolts.
Ya hoo.

I worked in a machine shop once and actually ran a bore hone. I found the lighter the pressure the more round it came out. It just takes longer. That may be the reason it took me 2 hours and not just 30min. I think it is worth the time.
Bore grinding can leave three point,five point, and chatter in the bore that a hone can actually take out. I do know if you can not get them round it is best to have them bored out by a machine shop. Only if there enough stock left in the cylinder to do so. I read these can be bored out to 30 thousands over sized and I only took out about .0015. I got the 30 thousands over sized rings and ground the gap to size.

I am not too far from running it. I will mix the oil a little heavy for the start up. maybe a portable tank with thirty to one mix just to be safe. Then back to 50:1 in the boats tank.

http://forums.iboats.com/images/icons/icon10.gif

 

[Craig-]

Re: 1990 90hp quickstart?

Nice work, hope the JB does the trick. Should hold up to jacket pressure alone, not sure about heat and vibration. At least you will be able to see it if it leaks. You could have it tig welded but that area is a pretty thin cast.