CMB 3.5 ??

[ColumbiaRBoater]

CMB 3.5, are they any good, reliable? How do they compare to a K&B 3.5? Thanks for any info, Mike.

 

[EatMyShortsRacing]

I would take the CMB..... unless its a really really old one.

more power and more reliable than a K&B

 

[RIGGERMORTISE]

I would take the CMB.....  unless its a really really old one.
more power and more reliable than a K&B

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I have recently got two from Hobbysupplies in Victoria one 21LS inboard and one 21LS outboard. Parts are readily available and the pricing is very good.

my 2c

dave

 

[ColumbiaRBoater]

Thanks for the info guys. there are two new ones on ebay, I have no idea how old they are and I don't know how high his reserve is but but I'll give it a try.

 

[MarkScott]

Mike,

Just a thought. What boat will the motor be mounted on? Inboard or outboard? Just wondering since if you are going OB, then make sure you have a boat that will handle the power of a CMB. If you are, others out here can comment on what will work for ya.

Mark.

 

[ColumbiaRBoater]

I have a Prather 31" deepv inboard. The crank broke on my K&B and I've been trying to find a replacement that matches my available funds, mostly PayPal gift certificates.

 

[[email protected]]

The guy selling them is Kevin Sharen, he's on the board. I'm sure they are in good shape but they look like real older styles, which is no biggie as a play engine. I have a CMB red Head, the older version and it runs really fast.

 

[Ron Olson]

Grimmie is selling the Green head .12's. I've seen complaints on those of leaking O-rings around the high-speed needles so some peoplle switched them over to remote needles. I don't know if that problem has been taken care of or not. If you get one, get the CMB TT tuned pipe to go with it, it's the quietest pipe that I've heard.

 

[TomMoorehouse]

Grimmie is selling the Green head .12's. I've seen complaints on those of leaking O-rings around the high-speed needles so some peoplle switched them over to remote needles. I don't know if that problem has been taken care of or not. If you get one, get the CMB TT tuned pipe to go with it, it's the quietest pipe that I've heard.

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green head .12's alright i have to get one

 

[NAMBA860]

I JUST BOUGHT ONE OF THE CMB FROM KEVIN THAT HE HAD LISTED ON EBAY IT IS THE GRAND PRIX MODEL OLDER BUT BRAND NEW IN THE BOX THESE ENGINES MAKE A LOT OF POWER I HAVE THE OLD CMB 90 GRAND PRIX I STILL RUN TODAY PUSHES MY 39 INCH CAL CRAFT MONO AT 63 MPH ON GPS.AND IT JUST RUNS AND RUNS AND RUNS. ALSO BOUGHT KEVINS 33 INCH CAL CRAFT HE HAD LISTED AND WILL BE PUTTING THAT CMB .21 IN IT.

 

[EatMyShortsRacing]

I have some spares for older CMB engines..... especially GP / Valvola engines....

anything you need just post it here....

 

[TimD]

Steptoe and son of the model boat world!

 

[Ron Olson]

OK Tom, you caught me in a Typo! I can spell really well but my typing isn't up to snuff. Usually I recheck my responses before I hit "Add Reply". BTW, I do that Typo a lot.

Steptoe and Son, the foreign version of Sanford and Son. I knew that!

Trivia: The name was changed for the American version, the British version was first. Redd Foxx's real last name is Sanford so they used that for the show.

 

[[email protected]]

The 2 CMB 3.5 red heads I had all leaked at the O-ring in the carb and neither needle would close all the way. I had to take that part out w/the needle and insert the basic nipple and use a third needle similar to what Ron was saying.

Eat My Shorts,

do you have a insert nipple for the red head carb? I had a spare from my MAC but..........the ground fairy swallowed it when I dropped it.

 

[EatMyShortsRacing]

Eat My Shorts,

do you have a insert nipple for the red head carb?  I had a spare from my MAC but..........the ground fairy swallowed it when I dropped it.

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I'll have a look. Can yo usend a pic of the carb and I can work it out from there. But if the MAC part fits it then I think my stuff will be a lot earlier. I have a lot of parts from the original Valvola engines (including probably a couple of complete engines). They are the silver head ones.

 

[TimD]

Rodney,

I think I have one - I will have a look and if I find it - it's yours.

Tim.

 

[Watercadet]

Eat My Shorts,

do you have a insert nipple for the red head carb?  I had a spare from my MAC but..........the ground fairy swallowed it when I dropped it.

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I'll have a look. Can yo usend a pic of the carb and I can work it out from there. But if the MAC part fits it then I think my stuff will be a lot earlier. I have a lot of parts from the original Valvola engines (including probably a couple of complete engines). They are the silver head ones.

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Do you have enough parts to Valvola assemble a "MAC Green Head?" Different intake I know. And what was the other thing that makes them run in the right direction?

Adam

 

[[email protected]]

Your right the MAC part doesn't fit my CMB .21 red head carb. The one I have is bent anyway.

Here's a picture:

 

[crrcboatz]

I have a 3.5 Grand Prix done by Rod Garathy and it will run VERY WELL. Has a K&B drum rotor, Nova Rossi head and work on the sleeve. With the steel rod it is not completely bullett proof but will last a long time.

Regards CUrt

 

[EatMyShortsRacing]

Eat My Shorts,

do you have a insert nipple for the red head carb?  I had a spare from my MAC but..........the ground fairy swallowed it when I dropped it.

81028[/snapback]

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I'll have a look. Can yo usend a pic of the carb and I can work it out from there. But if the MAC part fits it then I think my stuff will be a lot earlier. I have a lot of parts from the original Valvola engines (including probably a couple of complete engines). They are the silver head ones.

81092[/snapback]

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Do you have enough parts to Valvola assemble a "MAC Green Head?" Different intake I know. And what was the other thing that makes them run in the right direction?

Adam

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Now that is an interesting question. The main difference as I understand it is in the drum timing. The Valvola had a different induction system like the Rossi 45 Drum. I have a couple of these drum inductions and I will have a look to see if they will fit on the new engines. I also have a few drums made up MAC style to fit the old Valvola engine as well.

Let me look into it