1991 V135 - Project Engine

Hi, my name is Steve and I'm a Mercury outboard restoration junkie.
My latest fools errand is a 1993 V135 that runs at idle but won't accelerate. I'm picking it up tonight site unseen for $600.00. The fellow that has it only lives a few miles from me and in a neighborhood that I once lived. All is good and he's willing to start the engine for me if I want.

Worst case scenario, I part it out. There are a few NLA parts on it.

Watch this thread to see how the saga of the Merc addict and his engines turns out!

Oh shoot, if this engine runs then I'll have three engines and only one boat.. We'll just have to do something about that! Watch the boat resto thread for my 09-10 winter boat project. It just might be a Toon!

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

Took a short 15 min jaunt over to the sellers house and found it sitting on the back of a Bayliner. The boat was not too bad but the transom felt pretty well shot. All I wanted was the engine so he hauled the boat over to my house and we pulled it off in the driveway. I've gotten so much use out of the inexpensive Kragen 2 ton engine host that it's paid for itself several times over. I highly recommend that if you're into doing this engine repair gig, you gotta get one.

Anyway, the engine has gotten warm but not enough to blister any paint. There is some fried wireing but nothing that isn't easily replaced. The advance module is fried and the vacuum lines are a bit confused but other than that it looks to be in fairly decent shape. If nothing else it has a top of the line Merc Stainless prop on it that probably cost more than what I paid for the whole engine.

The owner said it runs fine and I think I can trust him on that. He seemed very honest and wanted me to know everthing he knew about the engine. He say's the only problem is that it just started not going anywhere when it was put in gear. The engine would rev but the boat wouldn't move.

After he left this evening, I put the engine in gear, pulled the prop nut off and gave it a yank. The prop spun on the hub so that solves that known problem. What, 45 bucks for a new hub.. Yeah I'm stoked.

This Saturday I'm going to start tearing it down so watch this thread. This time I'll actually take some pic's so we can all learn at the same time.

Current cost: $600.00 (I'll keep a running tab so you can see how much you might expect to pay to do a similar engine resto.)

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

8/26 - I pulled the lower cowl covers off and checked the powerhead to exhaust plate bolts. It is either a late 92 or a 93. 91's had 10 bolts this one has 6 if I counted right.

Removing the lower cowling ( engine removed from transom) : There are 4 screws that hold the two cowling pieces togehter. Two are forward and two are aft. Look closely because they are recessed into the cowling. Remove them using a 1/4" drive deep socket with an extension. The tell tale water tube can be disconnected either from the t-fitting or the cowling. I chose the t-fitting because it was easier to get to.

There are four rubber shocked mouting studs inside the covers. Starting with the port side, Use a wide flat blade screw driver to gently pry the mounts off of the studs. On the Starboard side there is a slip in exhaust tube at the back that needs to be removed and the fuel line fitting at the front needs to be unbolted. This is easiest to do if you pull the cover off the studs first then support it and disconnect these items.

Place the four securing screws in a plastic sandwich bag marked "Lower Cowl" and tape it to one of the cowl pieces.

Check inside the cowl covers for any nuts, bolts, screws, etc that may have fallen off. If you find any put them in a plastic baggy and label it "? Found in cowl" and tape it to the top cowl cover.

Now that the cowls are removed you can begin your preliminary inspection. Start by taking pictures of all the components as whole and close up and doing an initial discovery inspection. This is an inspection so if you find something wierd don't delve deep into it now or you will get sidetracked thinking you've found an easy fix when there may be other resultant damage that you'll overlook.

1. Look for burnt wires or wire covers.
2. Check that the throttle and timing advance linkage is moving freely.
3. Remove the spark plugs, labeling them with a Sharpie as to which cylinder they came from. Put them in a baggie and save them for later analysis.
4. Look for any obviously removed items and for the presence of prior owner modifications. Take pictures of these close up.

STOP.. Make sure your pictures came out the way you need them and re-shoot any that don't give you the info you want.

Download your pics to your computer and burn them to a CD. Print out the pictures that are needed to tell a complete story and place them in a binder labled in a manner that makes sense to you.
That's enough for the first session.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

8/26 - Having inspected the engine I found a couple of obvious problem areas. The wiring from the rectifier, the temp sensor and the temp switch were burnt from the outside and the factory head marking paint was discolored at #1 cylinder. This indicates an over temp problem. I inspected that plug and it was clean while the remaining plugs were slightly fouled with carbon residue. This was the cleanest of all the plugs so my suspicion is that it was recently changed. These are perma gap plugs and are not the ones that the manual calls for. I checked with NGK and verified that these were the wrong plugs. I can conclude from this that the plugs were an attempt to cure a pre existing problem. I then looked at the other obvious problem and that was the spring was broken on the throttle/advance linkage. The trigger was stuck about half advanced and moving the throttle did not change the advance position.

I returned to the port cylinder head and removed the head bolts. The bolts were not properly torqued and the thread sealant had been broken loose. This head had been removed before. I pulled the head off and found that there was aluminum on the cylinder wall of number 1, number 3 had wear and very light scoring and 5 was normal. I then went to the stbd head and found it had never been removed there was no evidence of an over temp on the exterior but the temp sender did show some signs of heat damage. The bolts on this head were still torqued to spec and the pop when they broke loose indicated that the thread sealant was still working. When I removed the head, all three cylinders showed normal wear and there was no sign of any damage.

With the preliminary inspection done, there is no need to even worry about the cause. A full rebuild needs to be performed. I'll start the full tear down soon.

The good news is that at this point the damage is actually minimal and provided the block checks good, a machine shop can take care of the cylinder problems. I may even get away with just replacing one piston if the bore remains standard.

Here's what a piston skirt meltdown does:



Close up:

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

8/27 - So looking at the pic's above we can see that the melted aluminum deposits are in the area of the exhaust ports and what I didn't see last night was that they are also in the area of the intake port. If you look at the top of the piston, it appears undamaged.

I'll lay some ground work - The starboard side is unscathed and the damage on the port side is progressive from the bottom up. The water from the water pump comes up the starbord side and then is tranfered across via a cross link hose to the the fill fitting on top of the port head.

The tell tale hose connects to a tee in the hose that feeds the starboard side. This is a bad design and I will correct it so that the tell tale comes off the 90 at the port head and install a pressure gauge instead.

What is the root cause of the problem ?

I haven't torn this engine completely down yet so this is speculative, but I beleive this is a classic example of why you should check your impeller frequently. This one was failing and because of that the upper cylinder (#1) was not getting enough coolant. The fact that the idle timing was advanced well beyond normal added the final component. The lack of serious scoring probably means that this occured when the engine was at or near idle and the cooling effect of the fuel was least effective. The hotter than recommended spark plugs probably were added after the fact in an attempt to keep #1 from fouling with it's low compression.

If I pull the L/U and find either a fried impeller or a new impeller I'll know for sure.

If any of you pro's want to comment, please feel free.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

8/28 - I started stripping down the engine and did find the original warranty for the engine behind the electrical plate. It's actually a late year model 91 with the 92-00 style block. Technically, I could call it a 96 because it wasn't sold until then but, in the 92 year production they added an accumulator and I don't have one. Oh well, I'm not too worried about smog anyway.

As I said before, looking for root cause is probably not worth the time. As I'm taking this thing apart I'm finding all sorts of rocket scientest mainentence. It's got the wrong fuel lines on it but I don't think the filter has ever been changed, lots of wires have been cut into and twisted back together, carbs are way out of synch, etc. the list just gets longer and longer. All this backyard wrenching was probably done without a manual and from the looks of the bolt heads, without proper tools either.

Folks, if there's nothing else you pickup from this post, learn that you need to use the rigth tools for the job. A manual is the first tool you need to buy! There is no doubt in my mind that if that rule had been followed I wouldn't be working on this engine right now.

I'm going fishing tonight, I'll get back on this thing next week.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

I built a new engine stand and have the power head and lower unit pulled off. Just as I suspected, there's a complete new waterpump in the L/U. Now there's a brainiac.. The engine overheats, burns a piston, melts the trigger to the block, cooks the rectifier and scorches half the wiring. So what's he do? He changes the water pump and takes it back out on the water. The entire waterpump is new so you gotta know it melted it down completely.

So there's today's lesson.. Change your impeller every season or at least once annually. More often if you run in salt or silt ladden water.

The power head comming off -


On the Bench ready to tear down -


Carbs pulled; note the numbering -


intake manifold -


Intake manifold removed looking at the back side; reed blocks -

Re: Special Note; 1993 V135 - Project Engine

Re: Special Note; 1993 V135 - Project Engine

Flywheel removed; note the marks on the stator -



And here's the trigger - Oooops



Crankcase cover -



Crankcase cover removed -



Reviewing my Pic's this morning I realized the problems with this engine are most likely the result of a culmination of induced problems. This is a classic example of why you should either have prior experience working on engines or take your engine to a truely qualified Marine Mechanic. I'll stop short of qualifying skill sets between 2 and 4 cycle engines even though I should.

Looking at what was done to this engine, I can speculate that the person bought a manual and attempted to fix it themselves. Unfortunately, they failed to comprehend or did not do all of the preliminary troubleshooting that is called for. The result of the effects of that on this engine is easy to see now.

If you are troubleshooting your engine and you don't understand the feedback your getting from the engine, ask questions. If you think you've found the problem don't stop there, finish the troubleshooting. In many cases you'll discover where the problem is really comming from or more potentially lethal problems that are a result of the initial one.

One of the biggest mistakes you can make with your outboard engine is to patch it up to finish out a season. If the patch works, you'll either forget about it or get complacent and figure it will still hold for next season.

Although this engine reportedly ran when I bought it and my initial finding was a spun prop hub, a simple compression test told me there's no way I should even try to fire it up. My test results were 100% correct and I trusted them so now I have an engine that is completly repairable instead of what surely would have been a total loss.

Finally, listen to your engines. They talk to you constantly. If you do, boating will almost always be a wonderful experience.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

8/31 - Lastnight I found the 5/32 12 point thin wall socket that I was looking for so I removed the rod caps, pulled the crank and the pistons.

Pistons really tell the story. #2 was also melting down when the P/O finally shut it down. There is some scoring on this cylinder also. The cylinders are all salvageable but a minimum of a .015 oversize bore will be needed.

The evidence clearly points to a failed cooling system as cylinders 3,4 are moderately worn and 5,6 still have the honing cross hatches. I haven't traced the complete cooling path yet and my manuals haven't arrived yet. Once in hand, I'll be able to understand exactly what went on.

After geting down to the bare block I located the block part number and sent an email to Merc Marine to verify the year and correct piston #.

The next step is to completely remove all the paint from the block, heads, crankcase cover and intake manifold. This is necessary for inspection since aluminum parts need to be checked both visually and electrically.

If any NLA parts check bad, this engine gets parted out and I go find something else to do this fall/winter. Moving forward with piston replacement is sketchy in my mind right now. 129.00 each may not be worth it. We'll see how the rods and crank check out. If they're good I might convince myself to go ahead with this.

The current total cost less time is still $600.00. I guestimate $2500.00 to be up and running again.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

Well, it's decision time. An inspection of the pistons and rods shows that two pistons are stock and four are aftermarket. The aftermarket pistons could be wiseco's they are numbered 3083P and 3083S (p/s = port/starboard). The Merc pistons are 755-7442 and the Rods are 636-8118 and are also not listed in the current parts lists.

Clearly this engine has had prior problems or.... it's a poorly done remanufactured powerhead. I found scrape marks from a metal scraper on the mating surface of the crankcase side of the block which in my book spells amature or non-certified mechanic. I'm not certified either but I do have some common sense and have been building engines since I was 12 years old.. Yes, that's true.. It was a 56 pontiac 318 and it ran when I was done. My Dad and I dropped it in a 39 Pontiac Coupe.

I found the date stamp on the block. It's 04 11 90 and that makes this a 91 and not a 93 block.

So the decision now is should I continue? A full new set of Wiseco's will run 880.92 with bearings.
The stator has blisters and you all saw the trigger so all the electronics need to go away. CDI replacements will run 1128.50 and that doesn't include coils, harnesses, starter, solenoids, bearings, block work, gaskets, carb rebuilds, etc. I now estimate the total bill to be more like 5000.00 and I have to ask myself if it's worth it.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

Great job on supplying information on teardown, I can get a complete rebuild kit for that engine for $1350. That includes:
6-pistons any size up to .040
1-gasket kit
1-crankshaft seal kit
1-upper main bearing
2-center main bearings
1-lower main bearing
6-wrist pin bearings
6- rod bearings (caged)

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

I was wondering when you were going to chime in.. Thanks for the parts offer. I'll PM you for details if you don't mind.

What do you think of Wiseco's pistons. I've been told they are the best. I can't get them in a matched set so the advantage of an out of the box balanced set is nil. I'd have to balance them as I would any other set.

By the way, do you think this engine ran a little out of balance with the mix of pistons....LOL... It's a wonder it didn't skin the skirts without the overheating problem. I haven't broke them down yet but I can feel the weight difference.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

I bought a complete set of electrics off'n a V6 on ebay for $150 about February. I got 2 regulators,stator, trigger, both switchboxes, oil alert, coupla timing modules, and a bunch of wires.

Used the stator, trigger, and oil alert so far. I'm well ahead of the curve. Judging from the butchery I had to do to use the oil alert module on an XR4, the stuff came off an EFI engine.

If you have time, that's the way to go for cost control.

hope it helps
John

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

j_martin said:

I bought a complete set of electrics off'n a V6 on ebay for $150 about February. I got 2 regulators,stator, trigger, both switchboxes, oil alert, coupla timing modules, and a bunch of wires.

Used the stator, trigger, and oil alert so far. I'm well ahead of the curve. Judging from the butchery I had to do to use the oil alert module on an XR4, the stuff came off an EFI engine.

If you have time, that's the way to go for cost control.

hope it helps
John

Click to expand...

Thanks John, If I do decide to go forward with this I would go with all new parts for piece of mind if nothing else.

I can easily recover my 600.00 investment parting this one out or I can throw cost to the wind and blueprint engineer this one into one screaming mutha.

Oh hell, I'm just gonna do it! Think I should turn it into a 150?

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

sschefer said:

Thanks John, If I do decide to go forward with this I would go with all new parts for piece of mind if nothing else.

I can easily recover my 600.00 investment parting this one out or I can throw cost to the wind and blueprint engineer this one into one screaming mutha.

Oh hell, I'm just gonna do it! Think I should turn it into a 150?

Click to expand...

Spend 2500 bucks turning it into a 150 and you'll have a .............$1900 dollar motor. If yer gonna do that, go get a real motor to start with.

used parts, tested out, are every bit as good as new. hell, my Bosch starter finally chit the bit after 20 years. New starter would be about $225.

I tore it down, had the armature refaced for $5, asked to dig in the used/junk parts and bought an 80% set of brushes and a good brush holder for $5.

Cleaned it up, oiled it up, and jammed it back together. It runs textbook perfect, including current draw test. Downer is I can only expect the brushes to last 16 years.

But, that's the way I do it.

My 02
John

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

O.K. Folks, here's the verdict, it's GAME ON!

I have a 100hp 91 Mariner that's going up for sale on Craigslist. That will help with the cost of making this engine right.

I'm buying either a North River or a AlumaWeld this winter and my new E-Tec 115 will get moved to it. This motor will go on my MonArk Legend 1800. I need to keep that one around for Tin-Stock 2010 in NY this summer. The plan is to sell it there so I don't have to haul it back. If I get enough to cover the trip expenses that would be fine with me.

So the plan is set and it's time to get going. I'll be going back to work prepping the block for the machine shop tonight.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

9/2 - OK Lets get back on track here.. I finally found a local machine shop that can bore these things. They're tough becuase technically it's a blind hole. Most machine shops have invested in boring bars and hones that need to go through the hole. In this case that can't be done. This block had rod guides that conceal 2/3 of the bottom of the hole and that requires a boring head and special honing stones.

The shop I found in my area is ALC Machine and they were recommended by our local "Boat Doctor". I still need to take the block to them to be sure they can do it but they've done quite a few Mercs and are pretty sure they can.

The cost is 125.00 per hole so combining that with possible head work and we're looking at about 1500.00 in machine work which is just about what I figured.

Just an FYI, I was quoted as high as 4,500.00 but when I got that quote I knew immediately that these folks had no clue so I moved on.

Just so you know, everything in the Marine Outboard Engine world is a mystery to most people. It is challenging to say the least but that's what makes it so rewarding.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

I personally do not use Wiseco pistons as customers dont not let the engine reach temp and they sieze and scuff. If I do use one I will bore cylinder .001 bigger than spec's. As balancing goes all pistons will weigh within a few grams of each other no matter what size they be. I doubt mixed pistons caused the problem, more likely preignition due to bad trigger.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

Worked on cleaning up the block a bit tonight. Didn't breakdown the pistons here's some pics of the work that needs to be done just preping it for the machine shop. I found over the years that the cleaner it is when you take it in the more appreciative the shops are and that usually ends up in a little extra care.

First here's the nasty #1 piston. Note how the ring is overlapped with aluminum from the piston. One discovery was made and that was that all the pistons are Merc originals. Some of them had the part number removed when the skirts were machined but on close examination you can see just the tops of the numbers. Replacing them is still going to give me the best end result because there won't be any doubt that the bores are in spec and any taper has been removed.



These are of the block after I stripped the paint off and cleaned it up with a stainless steel wire brush.





I've got some detail work to finish but I ran out of stripper so I'll knock that out tomorrow night and then take it to the machine shop on Friday.

Just in case your wondering how to get your water passages clean. It's an old wive's trick to use vinegar and water to remove calcium and lime. You cover or plug whatever you need to to get the block to fill up and then fill it with a 25:1 vinegar and water mix. Let it soak over night and all the calcium and lime deposits will simply dissapper. Do not use a product like CLR it contains citric acid and will damage the aluminum. Vinegar is also a citrus acid but at 25:1 it will not damage the aluminum. This also works on your shower heads. So there, you have a household tip as a bonus! Show this to your wife and she might let you buy something for the boat.

Re: 1993 V135 - Project Engine

Re: 1993 V135 - Project Engine

9/3 - New Tally:
Engine 600.00
Cleaning gear: 40.06
Manuals: 152.80

Total: 792.86

I finished cleaning the block and checked it for square. All is good so I hit the exhaust ports with oven cleaner and wrapped it up in tin foil to set overnight. I then cleaned up the heads and checked them and they are flat within .002 and that's fine. I hit them with oven cleaner and wrapped them up as well as the exhast baffle.

Next I started breaking down the pistons. No's 1,2,3 and 4 rods show signs of bearing wear on the small end. Bearing wear is when you can see horizontal lines accross the journal and I can on 1 and 2. No 1 is pretty dark indicating a lot of heat. The wristpins were blue on 1,2,3 and 4.. That's not good but I never intended to use them again. I'll have the rods checked and I hope I can save them. Them buggers aint cheap and will add another big chunk of change to the final bill if I have to replace any of them. If I can even find them.

Tomorrow the block goes to the machine shop for boring. I guess I better get the pistons ordered!