Budget d-mod build up

[blueskyracer]

Thats what I just found out on facebook to Brian. He runs with us. D Mod this year may go from 2 boats to about 6 this year. Just wanted more info for this post for anyone interested. How much does it cost Steve? Looks very nice.

[pav225]

Mod motor

This is awesome!

Great idea!

[maverick]

Thats what I just found out on facebook to Brian. He runs with us. D Mod this year may go from 2 boats to about 6 this year. Just wanted more info for this post for anyone interested. How much does it cost Steve? Looks very nice.

Per Request,

This is the kind of thread that get people motivated on building up a class. We have to put aside our own agenda sometimes and contribute for the whole as its no fun just watching one or two boats running a heat. Thanks Dale!! I hope you can come back to Moses this year?

This is the motor that will get the Steve Roskawski ignition.

Brian
maverickracing@q.com

[blueskyracer]

Per Request,

This is the kind of thread that get people motivated on building up a class. We have to put aside our own agenda sometimes and contribute for the whole as its no fun just watching one or two boats running a heat. Thanks Dale!! I hope you can come back to Moses this year?

This is the motor that will get the Steve Roskawski ignition.

Brian
maverickracing@q.com

Lucky motor it gets to live in the house?

[FER-R-10]

Torque specs

Here are some torque specs I found, from Ron hills sight, Might be helpfull, they helped me,


Mercury 44XS & Older 4 Cylinder Torque Chart:

Tighten in stages, 1/3, 2/3, then just below spec, then at spec.

Connecting Rod Screw (New Screws, do not reuse) 18 Ft. Lbs. Red Loctite 271
Older motors, bolt & nut (new nut recommended) 18 Ft. Lbs. Red Loctite 271
Center Main Bearing Retainer Screws 10 Ft. Lbs. Red Loctite 271
Replace screws with Gr. 8 Allen & AN washer, Loctite Quickmetal Race to Retainer
Reedcage Screws Max. Hand Tighten w #3 Phillips Red Loctite 271
Older motors, brass reedcages Max. Hand Tighten w #2 Phillips Red Loctite 271
Reed Mounting Screws Max. Hand Tighten Green Loctite 290
Older motors, brass reedcages 30 Inch Lbs. Green Loctite 290
Crankcase Bolts: 18 Ft. Lbs. No Loctite
Seal cover to block with extremely light coat of Loctite 518, ooze indicates too much
Bearing Endcap Bolts 16 Ft. Lbs. Blue Loctite 242
Center Main Bearing Bolt 18 Ft. Lbs. Red Loctite 271
Reedcage Bolts 12 Ft. Lbs. Red Loctite 271
Exhaust Cover Bolts, 5/16" 16 Ft. Lbs. Blue Loctite 242
Older motors with 1/4" bolts 10 Ft. Lbs. Blue Loctite 242
Port Cover Screws 10 Ft. Lbs. Blue Loctite 242
Powerhead Nuts 16 Ft. Lbs. Blue Loctite 242
Switchbox Mounting Plate Bolts 10 Ft. Lbs. Red Loctite 271
Stator Screws* 60 Inch Lbs. Red Loctite 271
Carb Nuts (New Gasket, do not reuse) 36 Inch Lbs. Green Loctite 290
Coil Cover Screws 24 Inch Lbs. Green Loctite 290
Switchbox Screws 30 Inch Lbs. Green Loctite 290
Fuel Pump Screws, #12 screw 36 Inch Lbs. Green Loctite 290
Older motors with #10 screws 24 Inch Lbs. Green Loctite 290
Flywheel Nut** 75 Ft. Lbs. Red Loctite 271
Throttle Linkage Bolts 16 Ft. Lbs. Red Loctite 271

Mercury "D" gearcase cone nut 125 Ft. Lbs. Anti Sieze

[blueskyracer]

some more great info. Thats just the kind of stuff we need

[PRO-MOTIONRACING]

Carbs

I'm back, great day of dirt biking. Not a race just a fun day of practice, some times it's great to just get out and blast away the clouds.
Next installment in our D-mod budget build, carburetors. On this 40 we will be using the KA carbs, I have seen other carbs used including those big carbs off of a Merc 650 but on this we want to be sure to keep all the torque. After removing the choke assemblies and a basic disassembling and cleaning, I remove the main jets, I have seen jets seize and break off so check before committing to a set of carbs. I then, in accordance with APBA rules make for "full butterflies" this is done by removing the butterflies and soldering them in. First I tin them with a propane torch then building up the areas to be filled in with a soldering iron. I then finish them up by shaping them with a belt sander. When re-installing them always use red Loctight on the screws.
As for the fuel pump and lines the stock ones works good for me I just go through them clean and inspect and replace gaskets as necessary.
When it comes to jetting... well I cant give every thing away here on HR but if you ask me at a race sometime I will be glad to share. Just remember bigger = cooler and cooler equals less detonation and less burnt pistons. But the moment before detonation is the moment of optimum performance.

[trident]

44 Tech Info

some more great info. Thats just the kind of stuff we need

You're welcome.

Its all out there...

Lots more 44 info posted in the '44XS Secrets' thread on Ron Hill's BRF.

Jerry

[blueskyracer]

You're welcome.

Its all out there...

Lots more 44 info posted in the '44XS Secrets' thread on Ron Hill's BRF.

Jerry

I started looking at it once but sounded like it was all about a stock 44XS so I did not read anymore. Then the pages got so big I could only see a couple words on the screen at a time.

I must say that these pictures really help. Already waiting for the next installment

[blueskyracer]

I have a question, why is the rope pulley so small on these motors? Seems as hard as they are to start that a bigger diameter pulley would help. Or is it because of the nasty kick back.

[pro350hydro]

I have a question, why is the rope pulley so small on these motors? Seems as hard as they are to start that a bigger diameter pulley would help. Or is it because of the nasty kick back.

Multiple reasons, but every one has there own theory and preference. For one, you can spin the motor faster with a small pulley which helps with the self energizing ignition. 2nd, Being a 4 cylinder, the motor will balance well. Meaning, you don't need much on top to absorb any nasty harmonics like you'd find in the OMC triple, that always has 2 pistons heading, in the opposite direction of the third. The theory of heavy and light flywheel/ropeplate can last for days as everyone has there own preference and/or theorys. Good thread so far, keep it up

[form-e one]

mike they not hard to start if you pull more than twice on rope something wrong,,, if you dont wrap rope more than one wrap on small flywheel you ok,,,small flywheel lets it spin up faster,,,but we already at speed usually by the time the race with westby's we running 44xs style flywheel and starter,,, no lag,,, as you know i run stock 11lbs flywheel on my rude gotta luv the old man push button start

[blueskyracer]

mike they not hard to start if you pull more than twice on rope something wrong,,, if you dont wrap rope more than one wrap on small flywheel you ok,,,small flywheel lets it spin up faster,,,but we already at speed usually by the time the race with westby's we running 44xs style flywheel and starter,,, no lag,,, as you know i run stock 11lbs flywheel on my rude gotta luv the old man push button start

You got the old man part right!

[PRO-MOTIONRACING]

PisToNs

With the block prep done it is time to look at the crank, rods, pistons and reed cage assemblies. Once again this motor was in very good condition so little attention will be necessary in this area, there was one slight scuff on one piston so I dressed that ring groove with a screwdriver to make sure the ring was not binding. I also checked the ring tension by just looking at the end gaps and squeezing the rings, all looks good. I then use a combination of bubble wrap and tape to cover the crank while I take the piston tops to the wire wheel. These are the flame slot pistons, I would prefer they were the more flat top pistons but this is the budget build up. After the wire wheel I then use WD-40 to soften any carbon in the ring grooves and with the rings still installed I run a broken ring through the grooves to clean them out, a little more WD to wash things up, good to go.
This motor had the small port brass reed cages, for high performance applications I prefer the large port aluminum cages, so it's off to the pile again. Some say that the carbon fiber reeds are the only way to go, I have built a motor with the carbon reeds but have never ran it so I cannot verify that they are better and besides this in the low budget build so stock reeds it is. By the way I do not bend the reed stops or flip the reeds over in the interest of reliability.
With the rotating assembly ready and the block prep done so begins the ever so fun process of assembling the block with no ring compressors, get ready this will tax your patience and your fingertips. First line up all the rings with the alignment pins. Next I try to do the center pistons first when assembling these do not use screwdrivers to push on the rings, I use popsicle sticks, and the popsicles cool me off when I get frustrated. Do not force anything, there is no need for a hammer, check that the ring gaps are aligned with the piston pins constantly and lastly a little bit of side to side action helps to roll the pistons in. Almost forgot, put those three alignment dowels in the block before the crank and feel for the reed blocks and center bearing to lock into them when the crank is pushed down into the saddles.
On this motor, as every thing is original and the end cap bearings are great and the end play is fine but if any of these parts have been replaced this is when I check the end play. First by installing the end caps with the front cover off and then I pry side to side on the crank checking that the crankshaft weights are centered between the reed stops and finally the total end play and shimming accordingly. I do not know what the end play should technically be, but I do know what it should feel like just a little clunk when moved up and down while still centered between the reed stops. This one is good so I will go with that, double checking upon final assembly.
A few final thoughts on the final assembly. Spin the motor by hand, it should spin freely, push up and down against the free play while spinning, make sure nothing hits. If at any time during assembly if anything does not feel right stop and go back and find out why, even after it is all torqued up. better to check it now. than have it fly apart and bust your block.
Lastly I use silicone sealer on the block mating surfaces and in the o-ring area on the end caps. Also when mounting the front cover I check the carb opening to reed block alignment and give a little tap as necessary.
One last thing I have included a photo of those parts I cut off the end caps back in my first post, this makes it fit other towers and easy to change the timing belt.

[krazy karl]

Installing Pistons

After years of using every combination of bad words I can think of to install pistons in a 4 cylinder I came upon a method that works quite well. Two small pieces of aluminum secured to a piston by a hose clamp. The picture below will show it better than I can describe it. The metal strips are aluminum so the piston will not get scratched. Tighten the hose clamp just enough to hold the rings down to the piston surface but not so tight that the strips of aluminum and hose clamp won't slide off the piston. Make sure the rings are aligned correctly and push the piston into the bore. You may have to loosen the clamp slightly as you go. Using a hose clamp with a hex on the tightening screw will allow you to get a wrench in to tighten or loosen. Put the screw assembly portion of the hose clamp on the intake side of the piston as there is more room on that side of the block.