1991 V135 - Project Engine

[sschefer]

Re: 1991 V135 - Project Engine

04/09

Cut a fat hog today. Took the block down to get it bored but the shop couldn't do it. So, I took it back home and pulled out a set of old diamond 220 stones and went to work. All the cylinders cleaned up nice so I took it back to the shop and had it checked. Max taper was .0005, (.006 is spec), out of round was .0005 (.006 is spec). Worst cylinder was 3.1262 (3.125 is stock). I payed the man, thanked them and took it to another shop and had it checked. The results were the same so I went back to the first shop and dropped the heads of for surfacing.

Dropping the cost by an instant 750.00 makes it more reasonable to continue. Now I just have to find a set of pistons. iBoats has the Mallory which are GLM's. They're O.K. from what I hear and they aren't horribly priced. I think I'll order them right now.

Oh yeah, here's what they look like now -

Remember this one, it's #1

Here's the block all cleaned up -

Ka ching.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/6/09

 

[sschefer]

Re: 1991 V135 - Project Engine

9/6/09

Pistons are becoming an issue. Seems the fact that my bores are clean and standard makes it difficult to find a piston. The port pistons are out of stock but there are plenty of starboard pistons. Of course, that should tell me something about these engines as to which pistons are most troublesome. #1 is the fried piston and of course, it's on the port side. I started another thread to see if I someone here has a line on them. Merc's site shows that I can order them but I'm not a dealer so I have to go through MarineMax and would rather not. If I go that route, I'll go through Crowley. They've been very dependable.

So, in the mean time today I mixed up some Mercury Phantom Black Acrylic Lacquer and shot the block, case cover, intake and exhaust plate.

I hit these with Zinc Chromate primer after washing them with lacquer thinner and blowing them off with air.

Tip: To get nice clean edges use a small file to gently remove excess tape around the edges. Remove the tape after letting the paint dry for only a few minutes. Lacquer dries quickly and hard. Leaving the tape on for any length of timed will make it very difficult to remove.

Safety Tip - When working with sharpened scrapers tie your free hand behind your back or you'll soon find your finger wrapped in duct tape like mine is right now.

Here's where we are after today -

This one came out a bit fuzzy and I did sharpen it but it's not the best.

Freshly honed cylinder sleeves are made of high iron content steel. They will begin to rust almost immediately so coat them in two cycle oil. Refresh the oil regularly during the build.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/8/09 -
Good news, the piston dilema is solved. I found a full set at eBasicmarine.com (Basic Power Industries). Actually, they are comming drop shipped direct from GLM. The other good news is that Wiseco responded to my frantic emails and cancelled my order this morning.

Now that the must be replaced with new parts are in the shipping process I can start ordering the rest of the parts. There's no sense in ordering anything if you can't meet the minimals. Keep that in mind if you do this type of rebuild. The first thing after identifying parts to be replaced is to find out if you can get them. If you can't then it can be a show stopper. You should actually do that before you even buy an project engine. I'll put that in my final how to thread when this is done.

I will not be ordering parts yet, I still want the piston kits in hand and I want to make sure they are correct before I proceed.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/9/09 -
I said I was not looking for root cause but I ended up finding it anyway. Have a look -

This is a dry stack. I think it may be installed backwards. Notice where the exhaust hits the water tube at the extension sleeve (this is a XL engine). Either that or it's a dry stack for 20" engine.

This is the water tube, notice the bubble in the middle of the extension connector. Thats has a hole underneath it the size of a half dime.

I now doubt the water pump failed and this was probably not done by the last P/O. Obviously someone was trying to make this a go fast motor and when it blew they sold it. My imagination can go on forever as to possible repair scenarios but obviously nobody thought of looking into the mid section. Funny, I guess they must have thought mid sized engines are supposed to be loud.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/9/9 Update - Heads are done, only needed to take off .002 to get them flat. Really didn't have to do that but figured what the heck, it's one less thing to wonder if I should have done. I'll post pics tonight.

Just ordered the new Exhaust tube parts. 348.00 to fix a mess. When I was ordering the parts I found the tube was available in two sizes and there was no part number for the connector. It's just 1/2" type L copper but it tells me that the just make something work method was in force here too. I think the original goal was a 20 to 25 conversion.

Revised root cause. Yep, I'm back to the original assumption that the impellor went south. The reason is that you can't even begin to solder a copper pipe with water in it so there's no way that it got hot enough to melt that splice piece if there was water running through it at normal volume and pressure. If there was a blockage and the pressure rose dramatically then yes but I think the volume dropped, the cylinders went lean. cooked the pistons, and the exhaust super heated and melted the tube connector.

 

[Zrt1200]

Re: 1991 V135 - Project Engine

I was looking at your honed block and noticed that none of the transfer or exhaust ports have a chamfer on them. I build racing 2 stroke snowmobile engines to pay for my hobbies. If you put small chamfers on the ports it will greatly increase ring life and helps to prevent piston scoring when the piston travels by the ports. It is a must!! Zrt.

 

[sschefer]

Re: 1991 V135 - Project Engine

Glad you noticed, most don't understand that production engines can be made to run much more efficently and last longer.

When they blow these things through a factory it's not cost effective to take the time to do these steps.

I haven't posted the latest pic's but I have smoothed the ports and had the heads milled .002. I'll be CC'ng and equalizing the head volumes this week.

As soon as the pistons arrive the crank, rods, pistons and flywheel are going in for balancing. I'm letting the shop put the bearings in the small end. It's not that hard if you have the right tools but they need to balance the rods first so might as well have them put them together and do the final weight test all in one shot.

 

[Zrt1200]

Re: 1991 V135 - Project Engine

I am glad to see you are balancing and CCing the heads.You will probable pic up 3-5 Hp just doing what you are doing (Blue printing). Have you thought about checking the port heights to see if they are the same?? A typical production engine very's .25-.5 MM per port per cylinder. Here is another tip if you do not know it. Take a medium to fine hand stone to your ring end gaps where it meets your cylinder wall and hone a small chamfer on them. This keeps the rings from grooving the cylinder when the rings wear. From seeing what you are doing it looks like we are both gear heads!! Zrt.

 

[Zrt1200]

Re: 1991 V135 - Project Engine

What brand of pistons did you decide to go with??

 

[sschefer]

Re: 1991 V135 - Project Engine

I went with GLM's and got them yesterday. They look fine but I'll go over them with a fine tooth comb this weekend. GLM was the only one that had the Port pistons in STD size. If I would have over bored I could have gone with any brand I wanted to.

 

[sschefer]

Re: 1991 V135 - Project Engine

I am glad to see you are balancing and CCing the heads.You will probable pic up 3-5 Hp just doing what you are doing (Blue printing). Have you thought about checking the port heights to see if they are the same?? A typical production engine very's .25-.5 MM per port per cylinder. Here is another tip if you do not know it. Take a medium to fine hand stone to your ring end gaps where it meets your cylinder wall and hone a small chamfer on them. This keeps the rings from grooving the cylinder when the rings wear. From seeing what you are doing it looks like we are both gear heads!! Zrt.

Yep, and Yep. Used to buy my small block chevy rings .005 over and fit them myself using the same technique.

I equalized and smoothed the ports last week. It's not easy with these nearly closed cylinder bottoms. I have a 1/4 mini right angle die grinder that just barely leaves enough room to work but it got the job done. Knuckles are a little bloody but I'll heal...LOL..

 

[Zrt1200]

Re: 1991 V135 - Project Engine

I have a 1/8" 80 degree die grinder (Shunner). It nice and small and should be for $400. I bought it years ago and the only problem I ever had with it is I wore out the collet chuck. Blooded knuckles. I have been there. And yes we heal!! Let me know how the heads turn out as this out board stuff might be my new hobby!! Zrt.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/12 - The new GLM's checked out fine so I started working on the rods. Cleaning and checking is the first step:

Here's pic's

First we check to see if they are straight. Any more than .002 and the rod is considered bent. All of mine were straight -

Next we snap the small end of the rod in at least 4 directions. We're looking for out of round --

Each time we measure the snap gauge and record the readings -

All of the ends were round within .00025 so we can use these rods over.

Just as a side note, the rod bolts are 5/16 - 27 tpi and you'll play heck trying to find a tap and die to chase the threads with if you don't already have them. I did but I used to run a Tool Supply store in another life. You'll have to special order them and you do need them because you must chase every thread to clean out the old Loctite.

You don't need an expensive set of taps and dies, you can get buy with a cheap set of Harbor Freight's because you're only chasing and cleaning.

 

[sschefer]

Re: 1991 V135 - Project Engine

9/13/09

We had our first rain of the season. It's pretty early actually and we're happy to see it.

First off new tally -

Engine 600.00
Cleaning gear: 40.06
Manuals: 152.80
Piston Kits (6): 491.70
Chris Carson Reed Set: 115.00
Mid Section Exhaust tube replacement: 348.96
Power head and head gaskets: 166.34

Total as of today: 1915.76

Today's job was final preping the rods and getting them boxed up ready to go in for balancing. I smoothed and massaged #1 so it would be the lightest rod and the machine shop will take it from there. I usually do this so the shop has to match the rest to the one that I prepped. This way I get a lighter and stronger rod. Keep that in mind if you ever do this. I was taught to do it and have been doing it for years. Any decent performance shop expects you to give them guidlines for your engine and this is one of the way's you do that.

After that I decided to prep the reed blocks for the new reeds that will be arriving next week. Here's the process -

Of course the first thing is to take all the screws out and remove the old reeds the reed blocks are shown earlier so not point in repeating. Here's the reed block just after the first pass during the flatening process. As you can see the factory flatness leaves something to be desired.

After the first pass you have an idea of where you need to get. This one definetly needs to start at 400grit wet/dry sand paper. Please folks, don't use a file you'll just leave nasty galling that will need to be sanded out anyway.

The way to go about this is with a sheet of glass. I go to home depot and get their 10x12 3/32 window replacement glass and leave it in the carboard but I tape it in securely. I then put my sand paper on top of it and wet it with Mineral spirits.

Here's the way I setup my glass -

and here it is ready to go to work -

Once you have it flat with 400 grit, change to 600 grit and the finished product should look like this. Please note the releaving of the sharp edges in the ports. This is done by lightly touching them with 600 grit after the flantening. You want to do this to help stop turbulence in the reed block.

The reeds I took off of these are in pefectly good condition. If anybody wants them let me know and I'll throw them in the mail. It's a full set of twelve steel reeds.

Here's all 6 reed blocks ready for a new set of reeds --

The heads are all done now. Here's how they came out -

 

[sschefer]

Re: 1991 V135 - Project Engine

Here's a shot of the progress. The carbs will get done last becasue I need to know what the vacuum is before I jet the carbs. +.002 over stock should be the number but ya never know.

 

[Faztbullet]

Re: 1991 V135 - Project Engine

Make sure whoever trys to balance that crank knows what they are doing, a stock crank is good to around 6100rpms 6200-6400 its a little off and anything over 7000 needs checked. When we raced years ago only 3 companys in US could balance a outboard crank and most took between 350-700 grams of tungsten. These where usually 1/2 plugs welded into upper/lower crank throws and it wasnt cheep!!

 

[sschefer]

Re: 1991 V135 - Project Engine

Thanks I'll ask then how they'll be balancing it. There is a shop in my area that can do second order harmonic balancing but I don't really think it's necessary for this engine.

 

[Zrt1200]

Re: 1991 V135 - Project Engine

Can we see a pic of your polished rod??

 

[sschefer]

Re: 1991 V135 - Project Engine

Can we see a pic of your polished rod??

Sounds kinda personal... LOL.. I don't go all the way to polishing them. I just use a die grinder to smooth out the sharp edges left from the casting. I just taking the extra time to finish what was started at the factory.

Removing sharp edges significantly reduces heat and stress concentrations. Polishing them makes the slippery and is effective in an oil bath motor but in a two stroke it's not and issue. I'm of the theory that polishing actually reduces crankase fuel atomization in two strokes but then maybe it's just because I'm to lazy to do it.