60 degree looper150 HP rebuild thread

SparkieBoat

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Ok I started the rebuild yesterday. 3-21-12 day 1

The only number I can find on my block is 438419. it is on the drivers side of the block. I want to know if my block is a 91 or a later block. I am about to tear it down and just want to know exactly what I have. The number on the welsh plug is 34094131. there is no tag. I know the 91 block has some differences from the newer ones. It has heads from a 91 motor but they may or may not be the original heads for the block (head numbers are 0332544)

had about 1.5 hours to work. got the heads off and the carbs, got the intake manifold and throttle body off one side. I am having to take this motor apart to check behind the shyster that sold me this motor as a fresh rebuilt motor. I trusted him and did not check the motor out before I purchased it, now he will not talk to me or return my calls, so to save a trip to jail I just let it go and decided to rebuild my rebuilt motor. let this be a lesson, 1) do not ever buy a motor from Frank on Wilmington Island, 2) take your compression gauge and demand a test run even if it is your moma. Here are some pics and my compression readings.
1 - 100
2- 90
3- 85
4- 90
5- 95
6- 90

2 of the magnets is chipped. do I need to replace them??

0321021532.jpg0321021532a.jpg0321021552.jpg0321021552a.jpg0321021552b.jpg
 

car1568

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Re: 60 degree looper150 HP rebuild thread

Good luck with the rebuild Sparkie.

I'm rebuilding my 91 175 Intruder we can swap war stories.
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

LOL..yea, feel free to post your progress in here and ask questions as it will help me out too as we have basically the same motor. what was your compression readings??
 

j_k_bisson

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Re: 60 degree looper150 HP rebuild thread

I don't know if they are chipped you need to replace them, but are they supposed to be two pieces? Wouldn't this cause a huge WTF with the trigger? There would be a double spark due to two N/S pole pasing in such a small amount of time.

My magnets where chipped on the edges, Was told by Joe Reeves that it was ok as long as they where not loose. But do not know about two magnets instead of one........ Ask Joe he is the expert.....
 
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Re: 60 degree looper150 HP rebuild thread

I don't know if they are chipped you need to replace them, but are they supposed to be two pieces? Wouldn't this cause a huge WTF with the trigger? There would be a double spark due to two N/S pole pasing in such a small amount of time.

I don't have the experience of ever having dealt with this much (well, except just once on my engine which was purchased about 2 years ago, also from Frank Mathews), but I did have to learn a fair bit about magnetism in school. I'm not so sure it would actually make a double spark, but the magnetic flux (the amount of magnetism) would probably be reduced a good bit - it certainly can't help. Oh, also, these particular magnets don't fire the 'trigger' but they do provide the voltage used by the ignition to make a spark. The corresponding cylinders could definitely have a weak or intermittent spark.
 

car1568

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Re: 60 degree looper150 HP rebuild thread

LOL..yea, feel free to post your progress in here and ask questions as it will help me out too as we have basically the same motor. what was your compression readings??

1 - 3 = 100
4 = 100
5 = 60
6 = 90

She had leaned out and seized a few times.

The plan is to bore and hone block .030 new slugs and rings. It only has 152 hours on it so not sure if all teh bearings will need replacing will check those once I get the pistons out.
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

Second day of rebuild, got some office work done this morning, my dad called me with a clogged septic line, turned out a pine tree had grow roots in a place and I had to dig a 3 1/2 foot deep hole about 4x4 foot wide to be able to cut it all out and replace, my middle son had an out of town baseball game, got home at 1:45 and left at 2:30, then got home at 9. so nothing got done today..maybe tomorrow.

car, your bearings/crank are probably good..sounds like you need pistons. you may or may not need to bore. I would not bore unless it was needed. maybe all damage was kept to the piston..

as for the magnets, on a OIS motor they have nothing to do with the spark, it uses an optical sensor and a timing wheel on top of the fly wheel. the magnets only charge the stator. So I may just remove the fragments and let her ride.

good news is the stator looks pretty new. and it came with a brand new CDI power pack. I had to order a set of the gray plug wires though. CDI says you need to use them over the old black wires. also use only QL78YC plugs.
 

car1568

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Re: 60 degree looper150 HP rebuild thread

Second day of rebuild, got some office work done this morning, my dad called me with a clogged septic line, turned out a pine tree had grow roots in a place and I had to dig a 3 1/2 foot deep hole about 4x4 foot wide to be able to cut it all out and replace, my middle son had an out of town baseball game, got home at 1:45 and left at 2:30, then got home at 9. so nothing got done today..maybe tomorrow.

car, your bearings/crank are probably good..sounds like you need pistons. you may or may not need to bore. I would not bore unless it was needed. maybe all damage was kept to the piston..

as for the magnets, on a OIS motor they have nothing to do with the spark, it uses an optical sensor and a timing wheel on top of the fly wheel. the magnets only charge the stator. So I may just remove the fragments and let her ride.

good news is the stator looks pretty new. and it came with a brand new CDI power pack. I had to order a set of the gray plug wires though. CDI says you need to use them over the old black wires. also use only QL78YC plugs.

I will definately need pistons, I have managed to find a reputable machine shop to carry out the bore and hone. I will drop the block in next Saturday as I am waiting to get a socket for the rod bolts.

I had just recently replaced:
The power pack
The stator
The optical pickup
Leads and coils
New battery and battery leads
Rectifier/regulator

After this rebuild it will be almost a new motor, I hope to get a good 10 years out of it :)
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

probably get more than 10 years, depending on how much you use it. what socket do you need for the rod bolts??
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

ok day #3, I got the rest of the intake manifold and crank shaft cover off. here are a few pics, I noticed a few scrapes on the number 4 crank shaft cover slot. could have happened before rebuild. I will have to get the socket for rod bolts.

0323021008.jpg0323021008a.jpg0323021009.jpg0323021009a.jpg0323021011.jpg



what should I do next??
 

j_k_bisson

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Re: 60 degree looper150 HP rebuild thread

What's up with the top seal. The tensioning spring is falling out?????
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

yes it fell out when I removed the crank shaft cover. I got the rod bolts all out. How important is it that I keep the rod caps and bearings all separate so that I do not mix them up? I just saw 020 on piston number 5, that is the new one. now I know why the number 5 cylinder got the lucky new piston. I guess it is bore time and new piston time. How do I remove the crank shaft??

0323021109.jpg0323021110.jpg0323021110a.jpg

o yea, the crank shaft cover did not have any gasket, only some type of gasket sealant.
 

j_k_bisson

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Re: 60 degree looper150 HP rebuild thread

It is very important to keep everything together. They match each other. What I did was semi bolt everything together, rod caps that is, Then put the cage bearings together inside and then zipped ties them to the connecting rod. Did not want to have to pay for new ones. They are reuseable, Also go to the dollar store and buy 2 boxes of extra large zip lock baggies. Put one piston and cage bearing set into one bag. Make sure they are sprayed with 2 stroke oil heavitly. This will cause the pistons from banging together and marking each other. Even if you are only reusing the connectinmg rods and the cage bearings. Less parts means less money.

Sorry about the over bore. Is the one that he bored the one with the low compression. If so and you have to up the size. Then every hole needs to be done. Sorry, 0.020" max difference between bore sizes before they start effecting performance. Talk to Boobie and Faztbullet. They rebuild these things professionally. One of them does. They know what you can get away with reguarding bore size differences and the jetting afterwards......

Hope this helps.
 

j_k_bisson

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Re: 60 degree looper150 HP rebuild thread

Also with reguards to the crank removal. Did you remove the top and bottom main caps? If so it should just lift off. But you will need to overcome the flange sealant.
 

FlaCowboy

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Re: 60 degree looper150 HP rebuild thread

Sparkie,

I would mark the bearings and rod caps to each cylinder so they go back to the same place on the crank.
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

crank is now out. the # 5 was not the low compression cyl. I am hoping to bore the rest out to 020, and get all new pistons and rings. Faz mentioned plugging the idle relief port to raise compression. I assume a machine shop has to do that. Block is ready to go to the machine shop. now I just have to figure out who to take it to, or if it is worth driving/shipping out of town to a OMC machine shop specialist. I am thinking just to get all cylinders bored to match the 020 cyl, or go to all cyl 030..any machine shop should do. I did notice that a few of the sleeves appeared to be about 1/8" turned so they do not line up perfectly with the ports. is this a big deal or normal?

0323021211.jpg0323021212.jpg

I have all the bearings, pistons/rods and caps in a plastic bowl for each cyl. But I did not keep the bearings in the exact placement, I am not sure if you can tell which way goes up, so I may have screwed this up. Will I be able to overcome this? I am also not sure how to tell which side is up on the caps.
 

j_k_bisson

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Re: 60 degree looper150 HP rebuild thread

I don't know of any body down there that does it, must be a ton. But up here in the Michigan area there is only one guy I would bring it to. The way I found him was to call up the two sleeve manufactyuring companies LA Sleeve and the other one, Can't think of it off hand, but they both recommend him. You might want to do the same. Putting in a sleeve right requires a good machine shop. To be recommended by the manufacture of the sleeve company is something else all together. I would do the same even if you are not putting in a sleeve, they will know a reputable place to deal with. Two companies is a plus.

Also if you do not have to bore them all out then dont'. It just money you don't have to spend. Just have the clean it up with a hone job and a new set of rings. If it is in tolerence then save the money. My recommendation anyways.
 

SparkieBoat

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Re: 60 degree looper150 HP rebuild thread

so it will be ok to have just one cyl 020 and the rest stock???
 

FlaCowboy

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Re: 60 degree looper150 HP rebuild thread

Down here where I live I spoke with a machine shop and they quoted me a price of 45 bucks a hole (FYI) to bore my GT 150. I have mine all apart but I have not been able to get it to the shop...they are closed on the weekends...must be nice. As far as the sleeves being turned....I do not have a clue.
 
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