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632 motor

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632

I would like to recommend a few things: Owning an expensive engine is not worth putting at risk if you are not 100% sure what the problem is. I would do a complete tear down and inspection before you take a chance of inflicting more damage. You have already had catastrophic engine failure. I would suggest have the work preformed by a reputable engine builder That is experienced in building Marine high performance engines, Marine engines and auto engines are not the same set up even if they share most of the same components. .The set up you have been describing sounds like an automotive combination ,Dual carbs, mechanical lifter cam, 10.5 :1 compression. Boats sustain long periods of high RPM use where an auto drag engine do not. Mechanical roller cams are used by racers to prevent lifter bleed down for exact valve timing and performance from their race engine. These guys have deep pockets and rebuild or install new engines every race. They run their engines at High rpm without letting off and adjust valves in between heats. Trust me you don't have the drive or the hull to feel the gains of a mechanical lifter. You will not be able to run it long enough or hard enough to experience any lifter bleed down if you did have a hydraulic cam. You would blow that XR drive first. At 10.5:1 compression you are just beyond pump gas. You have to use octane booster witch is a poor solution to racing fuel or use racing fuel. If you use pump gas you will have to bump your timing down to prevent detonation and you will be de-tuning your engine to make it live. you can make more torque with the right roller hydraulic cam profile at a lower RPM with a single dominator carb. you can turn a bigger prop at a lower RPM at the same or higher speed. you have the cubes to do so. This will save you equipment and be dependable. Even if you have a big wallet why would you want make mechanical repairs and adjust valves, sync carbs pay for racing fuel, every time you use your boat. With the set up I'm suggesting you should be able to turn a 30 pitch prop and if you hit 5300 RPM you would be at about 100 mph that's with 15% slip.
So I am just giving some advice so you can still blow off the other guy lower your maintenance and cost to operate and enjoy your boat. I hope this makes sense and Please don't take this as an attack.

MKHammer
 
mkhammer said:
I would like to recommend a few things: Owning an expensive engine is not worth putting at risk if you are not 100% sure what the problem is. I would do a complete tear down and inspection before you take a chance of inflicting more damage. You have already had catastrophic engine failure. I would suggest have the work preformed by a reputable engine builder That is experienced in building Marine high performance engines, Marine engines and auto engines are not the same set up even if they share most of the same components. .The set up you have been describing sounds like an automotive combination ,Dual carbs, mechanical lifter cam, 10.5 :1 compression. Boats sustain long periods of high RPM use where an auto drag engine do not. Mechanical roller cams are used by racers to prevent lifter bleed down for exact valve timing and performance from their race engine. These guys have deep pockets and rebuild or install new engines every race. They run their engines at High rpm without letting off and adjust valves in between heats. Trust me you don't have the drive or the hull to feel the gains of a mechanical lifter. You will not be able to run it long enough or hard enough to experience any lifter bleed down if you did have a hydraulic cam. You would blow that XR drive first. At 10.5:1 compression you are just beyond pump gas. You have to use octane booster witch is a poor solution to racing fuel or use racing fuel. If you use pump gas you will have to bump your timing down to prevent detonation and you will be de-tuning your engine to make it live. you can make more torque with the right roller hydraulic cam profile at a lower RPM with a single dominator carb. you can turn a bigger prop at a lower RPM at the same or higher speed. you have the cubes to do so. This will save you equipment and be dependable. Even if you have a big wallet why would you want make mechanical repairs and adjust valves, sync carbs pay for racing fuel, every time you use your boat. With the set up I'm suggesting you should be able to turn a 30 pitch prop and if you hit 5300 RPM you would be at about 100 mph that's with 15% slip.
So I am just giving some advice so you can still blow off the other guy lower your maintenance and cost to operate and enjoy your boat. I hope this makes sense and Please don't take this as an attack.

MKHammer
Click to expand...
I have a local guy buy the name of Jim Bening that all he does is high performance boats,all day long at Advanced Marine..He is the guy that built my 540 years ago that i have never had a minutes problem with..H e came over the house and helped me diagnois the problem with the motor.He recomended many things, as far as pulling the motor and going through it to check everything,then dyno..Also by the looks of the oil filter insides,could put cam and lifters in it and keep an eye on it.We know for a fact that the lifters were the problem,because the oil ring on the lifter bairley exzisted.its a shubeck radiused lifter.I talked to the guy that built the motor witch hes a marine high performance motor builder,and he recomends put cam and lifters in it and ride,that they ,dont have anymore than 2 hours on that motor after freshening.I ordered a new comp. cam, and there newest roller lifters.I am hoping for the best of luck,and no more problems..
 
I wish you luck checkmate 632......that sounds like one bad azz mota! I know how frusterating little problems can be. I am still working on my 540.
 
I build engines for a living, I know its a hassle to pull one out. but it a lot cheaper then blowing it up. You will be pulling it out anyway and paying more to fix it.
Generally when a engine has a problem that's when they go wrong in the first 10 hours of running.
 
I hope the man can help you. But if he didn't build the 632 he doesn't know without taking it apart either. He can only make some educated suggestions and hope they work.
So good luck
 
Good for you it looks cool

I was in doubt because your posts were all over the place. Good for you it looks cool. I'm wearing sneakers again.

While you have it down check the push rod length. If you haven't already. Put a dial indicator on the valve spring retainer with the push rod and rocker in place on #1 intake, Take a sharpie and color the top of your valve stem solid. Rotate the engine by hand and measure half the cam lift on the dial indicator. at half the lift rub the rocker arm side ways back and forth on the top of the valve stem. It will rub a fine line in the marker .Remove the rocker arm and look at the valve stem. If your push rod length is correct the line will be in the middle of you valve stem favoring the intake port side. If is not, Get an adjustable push rod follow sequence again and adjust the push rod length until you get the rocker arm to lash where it needs to be. Put a caliper on it record the lenght. Repeat at exhaust valve. High quality custom lenght push rods will run you about 150 bucks. This is usually done with a light checker valve spring in place of the permanent one during pre assembly. I have seen mechanical lifter engines eat valve trains in large engines because the geometry was off. As for oiling you have restrictors in you gallies for the mechanical lifter. They can clog if the block was not cleaned a prepped right. Mechanical lifter do not need as much oiling as hydraulics. but they need enough to lubricate adequately. Just wanted to let you know how to do it in case you didn't.


Mkhammer
 
mkhammer said:
I was in doubt because your posts were all over the place. Good for you it looks cool. I'm wearing sneakers again.

While you have it down check the push rod length. If you haven't already. Put a dial indicator on the valve spring retainer with the push rod and rocker in place on #1 intake, Take a sharpie and color the top of your valve stem solid. Rotate the engine by hand and measure half the cam lift on the dial indicator. at half the lift rub the rocker arm side ways back and forth on the top of the valve stem. It will rub a fine line in the marker .Remove the rocker arm and look at the valve stem. If your push rod length is correct the line will be in the middle of you valve stem favoring the intake port side. If is not, Get an adjustable push rod follow sequence again and adjust the push rod length until you get the rocker arm to lash where it needs to be. Put a caliper on it record the lenght. Repeat at exhaust valve. High quality custom lenght push rods will run you about 150 bucks. This is usually done with a light checker valve spring in place of the permanent one during pre assembly. I have seen mechanical lifter engines eat valve trains in large engines because the geometry was off. As for oiling you have restrictors in you gallies for the mechanical lifter. They can clog if the block was not cleaned a prepped right. Mechanical lifter do not need as much oiling as hydraulics. but they need enough to lubricate adequately. Just wanted to let you know how to do it in case you didn't.


Mkhammer
Click to expand...
im vaerythankful for the help,me and chassisman primed the lifter valley last night just to see if the new lifters were getting oil around then like they should,and it was..ordered comp. push rods after sizing everything up next day air ,so we can go out on saterday.She should fly.
 
Does any of you guys ,know anybody that would be interested in the tunnel ram set up that i have,its the best of everything,for a tall deck?
 
well 632 i can man up and say sorry for calling you out.......your post were kinda mixed up like mk said....and there is a ton of 16 year old kids on forums saying they have crazy set ups or top notch crap. so its easy to think someone is full of it with no pics.anyway super nice 251, tho i still like mine better sorry thats just how it is when you spend a year restoring something
 
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