I would do the front bearing as well.
How much pinch does the piston and sleeve have?
Is there any excessive slop around the big end of the conrod and the crank pin?
It really depends on the condition of the engine as to how much rebuilding it needs.

The engine still has a very small amount of pinch with the glow plug removed, however it still has awesome compression with the plug in. As for the other questions, I don't really know. I dont really know much when it comes to engine internals in general so I wouldnt know what to look for.

what i would do is put in new frnt and rear bearings and check rod for slop and send piston and sleeve to rex welch (22racer) for pinch to be done or you can send him whole motor and he can go thru it . i think brian (mugen46) at pro twister mods is doing engine rebuilds also and has the bearings . i sent 2 motors to rex and they run AWESOME after fresh pinch thnx will g

As long as a motor has good compression with the plug in it is fine. Will thanks for the props but it looks like he lives in Australia, shipping may be a bit much.

Rex

good call rex didnt notice that my fault sorry gary d8

my .25 i got back from you finally loosing metal pinch and has better high rpms now wow it works well with that 0801 pipe i have on there with russells tuning it ran great at the last series race here in az

i believe theres a dealer in that area

http://www.massivemods.com.au/index.php

Hi Gary, the price of Go spares is very reasonable so if you are doing the rear bearing I would do the front bearing while your at it. The Go engines are super tight when new and not knowing the break in history of the motor I would throw a new rod in too. A lot of racers change the rod after break in at around 2 gallons just as insurance, because of the tightness off the metal pinch during the first gallon or so. After you put the new rod in you will get a very good run out of the 7 Port (up to 10 gal or more is not uncommon from a new motor). Strip it down and give it a check. The only other thing that springs to mind is the bottom (chocolate coloured) carb O ring that sits in the crankcase. These can get a bit shredded, so you might want to look at that. Seal everything up - carb, pinch bolt ends, back plate. Throw some fuel in it and stand back
If you need any Go parts or modding etc done, contact Mark at Massive Mods in Sydney. Go the Kiwi Rugby League Team !!!!!

Cheers Shane and everyone else. I appreciate the advice. I have heard that Mark is a good bloke to deal with and have been told excellent things about some of the power and incredible run times that the guys are getting with the MM Modded engines. I am a little hesitant to spend too much on this 7 port though as it will probably be used mainly as a backup motor for next year. I will definately replace the bearings front and rear though and check over the rest of the internals and carb and go from there.

Cheers,
Gary


Oh and MM, you've got mail.

I've got a Go 5 port which is just run in... about 2L thru it now.

In the last couple of days it has oil leaking under the flywheel ... seems to be coming out at the rear edge of the flywheel... which to me suggests a stuffed front bearing- or is that normal?

(After running one tank thru it is about errrr lets say half a mL of oil drips out. )

BTW it is in nice tune, it holds tune perfectly, still bit rich of course, but it will idle for 10sec and then pull away fast so not mega rich thus I think there can't be anything major wrong with the front seal it is not leaking air I guess... that is why I dunno if this is a normal thing

Hi Mark, not too much to worry about. Just a slight leak from the front bearing. A couple of my 5 ports have done the same thing, but ran on faultlessly. It seems the front bearings can weep a little bit on some motors. As long as the bearing feels soild it will be fine. If it starts running hot or loses it's tune repeatedly check that bearing first.

Right on !! Massive Mods is massive on service and Marks motors run HARD
A few of us Kiwi boys have had motors shipped across the Tasman, and we are all very impressed with the power and run times of the modded motors.
The new Gen 6 - Stage 6 modded motors will be unleashed by MM soon, so save your pennies and grab one of those when they hit the tracks.

Stage 6?!! I dont know if I really NEED that much Go. Would be fun though.

What motor/pipe does everyone recommend for a D8 buggy? 3, 5 or 7 port?

I'd go with the 5p. It's a safe bet as it has plenty of grunt down-low and nice top. 3p is more linear and 7p then has the top with a bit soft bottom. I'd combine the 5p with GO 2047 or the GO 0801 FEMCA pipe

Depends on the track you intend to run the most.
Very tight technical track with moderate straights - 5 port with 0801
More flowing track with moderate to longer straight sections - 7 Port with 053 or 0801
Generral purpose motor with nice linear response - 3 Port with 0801

I have never run the 3 Port, so can't give you an honest appraisel on that motor.

The stock 7 Port is a very nice buggy motor. Ample bottom end for a buggy, and top end to die for. If you are going for a stock motor, this would be my choice in a buggy no question.

Most of the race teams that use the Go engines run modded 5 Ports in their buggies. These modded motors have that mighty 5 port bottom end with extended top end like the 7 port. Pretty much the best of both worlds.

Now your totally confused - right

Hey Guys re leaky bearing, i had a client bring one in with that. I noticed a little weaping of oil, i checked the seal , best way to do it is to try to turn the seal with your thumb nail.. if it turns its time for a new one OR you can seal the outer edge with 262 loctite ( thats a bodge way to do it ) its a quick fix at the track really than a long term thing. Anyway i tested the engine in my buggy for 2 tanks and it ran fine . no front bearing is air tight , they all leak to varying degrees. So dont stress if you notice this happening. if the engine runs reliably then its not doing any harm.

Cheers MM

Re the Gen 6 Engines, I will be releasing a limited number of these through my site in the weeks leading up to christmas. Ill probably do a series of 5 of each engine as a pre release hand modified. They will be modified to the Gen 6 spec.

I will be adding an extra port to each one so the 3 Port R Spec will be a 4 Port G6 , 5 Port will be a 6 Port G6 and the 7 port will be an 8 Port G6. As well as changing the timing and balance of the entire engine. With the research we have been doing we have managed to really work on how to save, what i call, the " Energy Centre " of the engine. This works on a theory of harmony inside the engine. Rather than ceating more power, is make the power the engine already has , more useful, less wasted energy to create an energy efficient machine.

What this gives you is better tank time, more usable power , less internal wear. Flowing charachteristics of the engine are changed too. Less resistance to flow make for easy tunability and again less fuel consumption.

Cheers MM