Seized 25hp 2-stroke

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Way back when I asked you for the s/n it was for a reason, so we could get you the service manual online and the parts listing. We don't even know if it is a 2/3 cylinder.

There is a difference between being a bull in a china shop and being patient enough to try and salvage the engine. I still can't believe that you are so anxious to run this thing. At least getting the exhaust off you can have a look and feel to see if the rings are frozen or broken.

Have you at least dropped the LU to see the condition of the impeller before running it?

The wisdom of others on here would have shown you to soak, heat and tap the screws, gently working them to avoid breaking as many as possible.

However, if you must run it, go ahead, maybe you can succeed in damaging it even further!

Gerry

Hey, I wouldn't say I'm a bull in china shop!! I just didn't expect to encounter broke bolts....one was already broken, I did two myself. Once I realized that bolts were breaking, I decided not to remove any other parts!! Maybe it was used in salt water, or maybe the stuck bolts are just bad luck?? I'm not overly anxious, I just find time to work on it here and there between all the other honey do things and then my other toys that I probably should sell anyways . I hadn't been able to spend any time on it and last weekend in the evening I was left alone to do whatever I liked and was a little over zealous, oops. I won't wreck the motor...one can always heli-coil if necessary!! I'm way more experienced with broken bolt extraction than I'd like to be....although not with SS fasteners in alloy block, but I'll manage with a little help I'm sure!!

Serial is 0G63xxxx, 2 cylinder, 1998 model 25ELH, 6000 max rph, 25hp, 115#. Here is a website with parts listings and really crappy quality diagram scans http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=18583+94
Service manual would be much appreciated!! Thanx!!

I would like to get that exhaust off, but those two bolts that I can feel will break scare me...probably going to be doing so heli-coils already!!! Not looking to do a bunch of them though!! I'm trying to find my map torch.....

I think I'll go grab a compression gauge and check the cylinders. If they're good, do you think it's worth dealing with the stuck bolts to check on the pistons/rings?? I guess it would be bad to try to start it if there was a broken ring, but other than that, no harm if the rings were just worn. The thing is turning nice and smooth, which I can't believe, so I'm not worried that any bearings are bad...I can't hear any noise at all or feel anything grinding, but then again, I did put a good amount of pre-mix oil down the cylinders!!

I wish I could find my map gas torch!! I'll soak everything in PB in the meantime.

Thanx for the continued help!!!!

 

[sutor623]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

If the compression is good then no, leave the exhaust plate on. Why search for a problem (and make more) that isn't even there.

 

[sutor623]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Oh and you will need to check compression when the new head gasket is on (obviously).

 

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Chasing threads often works fine. You can send pics if you'd like. If the head is not down tight, with a fresh headgasket, water will not only squirt all over the place, it will find its way into the cylinders. Just do it the right way and wait until you get the head back on before trying to fire it up.

Doesn't look like there is a head gasket to me, only a water jacket. Looks like the heads are cast into the cylinders themselves....so no way for water to get in from this end. But I take it people generally don't think that this is a good idea, so I'll tell my bro no, we won't start it yet. We do want to see if it will start, but I guess it will have to wait until I can find the time to get everything in tip top shape.

Here are some pics, just because. Pic of the cylinder where it says mercosil from last week, before I had done anything other than pour tons of pre-mix into the spark plug holes.

Here you can see the exhaust manifold. All of the outside bolts were actually loose, almost 1/4 of a turn. they would all come out no problem, but I tightened them down. The two middle ones you can see where I had the socket on there....I loosened a tad, tightened a tad, and said F it, I don't want to deal with breaking off any more bolts!! The paint was untouched prior to me just doing this.

and here it is, the cylinder with the water jacket removed. Top left you can see the broken bolt from someone else...there was a wood screw holding the water pisser housing on....I guess it must have worked??? No wonder the previous owner didn't bother to check to see how seized this motor really was!! Then the other two broken bolts are me .

 

[carholme]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Here is the parts listing:

http://www.crowleymarine.com/mercury-outboard/368.cfm

Here is the service manual, P/N: 90-826883

http://1manual.com/Mercury manuals/Service Manual PDFs/TwoStroke/826883r2/cover.pdf

You must have Adobe Acrobat reader installed to use this manual. If you scroll down to the lower part of the opening page, you will see the various engine components in red. Click on the one you want and when the first page opens, click on the "Save As" icon at the top LH corner of the page and you can save it to your computer.

Gerry

 

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Oh and you will need to check compression when the new head gasket is on (obviously).

Check the photo, the cylinder and head are cast in together...not sure why. Same idea as one of my husqvarna chainsaws, 141, sucks because you can't deck the head to up the compression a bit, or deck the cylinder to change port timing. Oh well, this thing ain't getting modded anyways.

 

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Here is the parts listing:

http://www.crowleymarine.com/mercury-outboard/368.cfm

Here is the service manual, P/N: 90-826883

http://1manual.com/Mercury manuals/Service Manual PDFs/TwoStroke/826883r2/cover.pdf

You must have Adobe Acrobat reader installed to use this manual. If you scroll down to the lower part of the opening page, you will see the various engine components in red. Click on the one you want and when the first page opens, click on the "Save As" icon at the top LH corner of the page and you can save it to your computer.

Gerry

Thanx Gerry! that's a better parts listing, the diagrams are scanned in more clearly.

In the parts listings, cylinder block and cover section, numbers 23, 19, and 40...what the heck are those?? do they cover the transfer ports or something?? Maybe the manual will tell me!!

Oh, and no I have no dropped the lower unit yet....I guess I shouldn't trust that it has a new impeller seeing as one of the jacket screws was substituted with a wood screw!!

I have full adobe so hopefully I can save it all and make it into one big PDF, thanx again!!

Marty

 

[carholme]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Yes, they are just the transfer port covers and I certainly wouldn't trust the impeller, not for the time it takes to check it.

Gerry

 

[sutor623]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Check the photo, the cylinder and head are cast in together...not sure why. Same idea as one of my husqvarna chainsaws, 141, sucks because you can't deck the head to up the compression a bit, or deck the cylinder to change port timing. Oh well, this thing ain't getting modded anyways.

Hahaha, yeah when I want more performance from an outboard I just get a bigger motor.

 

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Sometimes I just cant leave well enough alone!!

So I got the exhaust cover off. Turns out three bolts were stuck and it was about 45 min each of back and forth, heat it up and blast w PB, then repeat but they came out. Pics to follow in an hour or so, but top cylinder looks great w a few little scratches, nothing major, I'd run it without a worry. The bottom of the bottom cylinder is fairly well scratched up and maybe I'm seeing some specs of metal on piston crown not positive. It looks like it will run just wont be 100% power from this one. Rings are free on both cylinders.

So, how hard is it to split the cases? If I'm gonna run into bolts like this the whole way through I may just put it together and run it. Assuming the pistons, which both looked fine and serviceable from what I could see, are indeed fine looks like 160ish for rings (woah!!!) plus gaskets etc and hone to clean it up if I don't need a bore. Anyone know of a kit w just one piston??? Any good full gasket kits out there or do I have to buy each individually?

Who says screw it just run it till it blows up??? That's what all my friends will say I'm sure.

Also, plugs look like engine was running just fine, no indication of lean jetting wise. Don't know if the scratched bottom of bottom cylinder is a typical no oil faoilure or what.....never run into such a seizure in my workings and ive seen quite a few seized up 2strokes. Pics to come this evening, thanx again all!!

 

[xjma]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Since the motor is no longer seized, I started a new thread with my inquiring about what the best course of action is now that I've begun opening up the motor.

http://forums.iboats.com/showthread.php?t=541649

 

[beads8]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

Way back when I asked you for the s/n it was for a reason, so we could get you the service manual online and the parts listing. We don't even know if it is a 2/3 cylinder.

There is a difference between being a bull in a china shop and being patient enough to try and salvage the engine. I still can't believe that you are so anxious to run this thing. At least getting the exhaust off you can have a look and feel to see if the rings are frozen or broken.

Have you at least dropped the LU to see the condition of the impeller before running it?

The wisdom of others on here would have shown you to soak, heat and tap the screws, gently working them to avoid breaking as many as possible.

However, if you must run it, go ahead, maybe you can succeed in damaging it even further!

Gerry

WOW Gerry...that's harsh dude.. LOL

 

[oldman570]

Re: Seized 25hp 2-stroke *Update* not seized up!!

Re: Seized 25hp 2-stroke *Update* not seized up!!

I do not believe it to be harsh to ask for info so we can help get the correct info to those that have asked for the help. If those asking cannot or will not give us the requested answers then we can not give them good info to correct they're trouble. JMO
Oldman570