The OS CZZ is back together, but will it run?

[ZED32]

Finally got my OS Max CZZ back together today. New rod from Hong Kong, new piston pin from Dubai. New OS 8 glow plug, Fasteddy bearings and new gaskets. The carb got all new seals too, and everything was cleaned thoroughly.

Then one idiot slammed it all back together. Is it right? Who knows?! But the engine holds some compression. Good compression? Probably not. Good enough compression? Hopefully.

This is what the piston and rod looked like before the rebuild. Same piston that it still has.

20240114_222124.jpg (34.94 KiB) Viewed 1767 times

20240114_222124.jpg (34.94 KiB) Viewed 1767 times

os engine 3.jpg (29.05 KiB) Viewed 1767 times

os engine 3.jpg (29.05 KiB) Viewed 1767 times

I have an air filter and fuel on order, so it will be ready to test in about a week. Prepared for it to fire up, blow up, or go on fire. Place your bets!
(Any tips on how to actually make it work are greatly appreciated. I have no idea what I'm doing)

[RC10th]

Wind the big silver needle all the way down till it's just snug, then back it off 2.5 turns

The needle that the throttle arm is attached to set that flush.

Set the idle speed screw so there is about 1mm gap in the carb.

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Will it be in a car, do you have a bump start box?

[ZED32]

Wind the big silver needle all the way down till it's just snug, then back it off 2.5 turns

The needle that the throttle arm is attached to set that flush.

Set the idle speed screw so there is about 1mm gap in the carb.

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Will it be in a car, do you have a bump start box?

Thank you for the tips! It will be in my rc10gt (just realized I lost the mounting screws...) but it's a non-pull start, so I do have one of those spiny starter things. It's not in a starter box, just kinda sitting there. Should I screw it down to some wood or something so it's more stable?

[jwscab]

Was the connecting rod a better fit on the crank pin on the new part? If not that is a major failure waiting to happen.

[ZED32]

Was the connecting rod a better fit on the crank pin on the new part? If not that is a major failure waiting to happen.

Yes, the new con rod is a perfect fit. The crank didnt seem to have any damage from the old rod so I'm not too worried about it.

[ZED32]

Yes, yes it will. Got it fired off for the first time. It ran horrible, but it moved. Accelerated, braked, steered. Got up to temp and seemed fine. The previous owner tells me it's the first time this car has moved in 17-20 years. It's kind of incredible to me, after seeing what condition it was in when I got it.

Now I need some help. It moves kinda fast at idle. I feel like it might be idling too fast causing the clutch to grab and move the truck? How do I slow down the idle? I have more questions, but I'll save them for once I get the thing to stop on my command, because right now my inputs are only suggestions. Thanks again RC10talk, you guys have helped massively through this build so far.

[romulus22]

A little long, but has all the tuning info you should need in here. I’ve watched this way too many times too admit.

https://m.youtube.com/watch?v=OJ29UqE0uS0&pp=ygUNcmMxMGd0IHR1bmluZw%3D%3D

[RC10th]

A little long, but has all the tuning info you should need in here. I’ve watched this way too many times too admit.

https://m.youtube.com/watch?v=OJ29UqE0uS0&pp=ygUNcmMxMGd0IHR1bmluZw%3D%3D

That's a classic

It's one you need to have a hard copy of.

[romulus22]

That's a classic

It's one you need to have a hard copy of.

I’ve got a few, no way to watch them anymore though. I was happy when I found the YouTube version.

[klavy69]

Now I need some help. It moves kinda fast at idle. I feel like it might be idling too fast causing the clutch to grab and move the truck? How do I slow down the idle?

sounds like you need to shorten up to the 1mm gap mentioned above by RJ with the idle screw. You have a picture of inside the carb at idle?

Another possability is your clutch shoes are sticking. Don't see pics of what you used but if they are the original clutch shoes you can clean them up/sand them on the contact side to get them to work properly or get an MIP 4n1 clutch shoe set and install.

Todd

[TRX-1-3]

Now I need some help. It moves kinda fast at idle. I feel like it might be idling too fast causing the clutch to grab and move the truck? How do I slow down the idle?

sounds like you need to shorten up to the 1mm gap mentioned above by RJ with the idle screw. You have a picture of inside the carb at idle?

Another possability is your clutch shoes are sticking. Don't see pics of what you used but if they are the original clutch shoes you can clean them up/sand them on the contact side to get them to work properly or get an MIP 4n1 clutch shoe set and install.

Todd

Do clutch springs get weak/sprung? My only frame of reference is distributor advance springs/weights and chainsaw clutches. Not sure how any of that relates to anything.....was just thinking if the clutch springs were "underrated". Do these things even have clutch springs??? -electric guy-

Sounds like you might just need to open the idle mixture screw a tad. Richen it up just a smidge. Better a little rich than too lean...

Base adjustment/settings are just a ballpark to get/keep it running so you can further/fine tune for your specific operating conditions, altitude, etc..

[ZED32]

?

sounds like you need to shorten up to the 1mm gap mentioned above by RJ with the idle screw. You have a picture of inside the carb at idle?
.

Todd

For one, I had the brakes adjusted wrong, so that definitely factored into it. I'll try shortening the idle gap, and too rich is definitely better than too lean.

[klavy69]

Do clutch springs get weak/sprung? My only frame of reference is distributor advance springs/weights and chainsaw clutches. Not sure how any of that relates to anything.....was just thinking if the clutch springs were "underrated". Do these things even have clutch springs??? -electric guy-

Sounds like you might just need to open the idle mixture screw a tad. Richen it up just a smidge. Better a little rich than too lean...

Base adjustment/settings are just a ballpark to get/keep it running so you can further/fine tune for your specific operating conditions, altitude, etc..

no springs in the stock setup but the MIP has a spring to retract the shoes if thats what you were after. the stockers just rely on the throttle to 'drive' and release the throttle to 'neutral'. when the shoes are 'dirty' they grip alot more not letting loose of the clutchbell under no acceileration. I know thats not a very technicle explanation but its what I got. Lol. MIP uses a spring around the shoes to retract the springs and since I never really cared too much about Preventative maintenance I used the MIP.

Todd

[guggles]

Does anybody have a parts list or a diagram of the carb seals for this motor?
I got one cheap off ebay but it needs a rebuild and the carb had no seals in it?

[RC10th]

What number is on your carb?

If it's the 2bk

http://oldrc.com/KyoshoFiles/OS2BKCarbManual.pdf