76 cyclone 440

[Grnx854]

Hello fellows, I just got a hold of 2 76 cyclone 440s. The sleds were running, kinda. The guy said he drove last year but ran kinda shitty so I went threw carbs and new fuel lines and tank ect... One sled runs, so I think but it always dies when I drive more then around the yard one time. I can idle it and rev it on stand ect for 10 min but as soon as I drive it, less then a block then dies and wont start. After I let it sit for awhile then same thing all over. Im thinking its my low speed coil but I have to go and test everything yet, just speculation at the moment. The other sled I did the same things to and just floods like a pig. My questions are this=1) what plugs do you guys all run? book says br10es , on here says ngk bue, but that seems way cold and I also read somewhere that these weak cdi's dont like them and to use non resistor ones? Ive always ran b8es in most of mine, like my jdx8, of course that doesnt have cdi but still, bue? 2) One carb looks normal like, but the other sled has some weird ball thing in the needle/seat area way different then the other sleds carb? Im thinking thats my whole problem but I dont know why one sled or carb is like this? They both seem to be the same mikuni carbs so idk. and 3) what the heck kinda fuel pumps do these things have on them. They look the same on both sleds(black plastic) but one sled its servicable and the other its not(solid) no screws to seperate it?

[JDT]

Crank seals may well fix both problems.

[WinnipegStPaul9]

Crank seals may well fix both problems.

Yep

DA

[jep_800]

I agree with the crank seals. But I'd also start looking at all your components in those carbs, and get the proper fuel pump. I had a sled that had dual mikuni's on it that ran like crap. When I started inspecting they were way off from factory specs. First thing is to get the service manual (can be found online) and see what each internal part of the Mikuni you're supposed to have (main jet, pilot, needle, needle seat, throttle valve, etc). I assume this would be a VM-34? Set it all back to factory settings, and then you'll have a much better baseline for tuning. Also look to see which fuel pump it's supposed to have. I believe Newbreed Parts sell brand new one's, or you can get the kit to rebuild it, if it is correct.

There is also many gremlins in the old Prestolite ignition system. You can test each component to see if it has the correct readings according to the manual... or just replace for new to eliminate your issues. You can replace the CDI, and then your old Prestolite stator may fall flat on you the very next time you run it. It costs a bit of money to replace everything, but if you ride it, it will save you a lot of trouble down the road. Hewtech sells excellent replacements for both CDI and stator. Ignition coils can be found on MFG, Newbreed, Pat's Small Engine, Dennis Kirk... all sorts of options.

I think the "normal" heat range plug for that engine is BR9ES. Actually, the CCW 440/22 engine originally came with Champion RN2. You can easily find RN2C's at parts stores, or they can order for you. From my understanding, these run just slightly hotter than an NGK. There are many that run BR9ES in their sleds with no issues. Hot enough to give proper combustion and less fouling, but not so hot that you'll melt your pistons from normal operation. That is... IF YOU CHANGE YOUR CRANK SEALS. Like Todd and Don stated, first and most important step. Hope this helps.

Jason

[Grnx854]

I agree with the crank seals. But I'd also start looking at all your components in those carbs, and get the proper fuel pump. I had a sled that had dual mikuni's on it that ran like crap. When I started inspecting they were way off from factory specs. First thing is to get the service manual (can be found online) and see what each internal part of the Mikuni you're supposed to have (main jet, pilot, needle, needle seat, throttle valve, etc). I assume this would be a VM-34? Set it all back to factory settings, and then you'll have a much better baseline for tuning. Also look to see which fuel pump it's supposed to have. I believe Newbreed Parts sell brand new one's, or you can get the kit to rebuild it, if it is correct.

There is also many gremlins in the old Prestolite ignition system. You can test each component to see if it has the correct readings according to the manual... or just replace for new to eliminate your issues. You can replace the CDI, and then your old Prestolite stator may fall flat on you the very next time you run it. It costs a bit of money to replace everything, but if you ride it, it will save you a lot of trouble down the road. Hewtech sells excellent replacements for both CDI and stator. Ignition coils can be found on MFG, Newbreed, Pat's Small Engine, Dennis Kirk... all sorts of options.

I think the "normal" heat range plug for that engine is BR9ES. Actually, the CCW 440/22 engine originally came with Champion RN2. You can easily find RN2C's at parts stores, or they can order for you. From my understanding, these run just slightly hotter than an NGK. There are many that run BR9ES in their sleds with no issues. Hot enough to give proper combustion and less fouling, but not so hot that you'll melt your pistons from normal operation. That is... IF YOU CHANGE YOUR CRANK SEALS. Like Todd and Don stated, first and most important step. Hope this helps.

Jason

That about the fuel pump is my main question as far as parts. Ive searched hi and low and cant find any conformation on what fuel pump is supposed to be on it. I would imagine a mikuni round like most others but not 100% sure thats all. I just cant believe someone or anyone would take the originals if it is round 52 type mikuni pump off both sleds and put something that I have never seen before on it instead of buy a $6 repair kit. As far as carb, yes is a vm34 but the other one has different internals for needle and seat for some reason. I have worked on many and have all the repair manuals ect... Im no newbee on this stuff just havnt owned every sled to say thats what it should have. Hell i even have manuals for multiple sleds makes and models and some info in those say one thing compared to the other sometimes, so its not a diffinitive 100% that it should have this all the time. But I do appreciate everyones input either way. Plus nice to make friends, ect... I will keep you all posted on results of tests since I havent checked much yet. Actually my brother took the carbs off and cleaned so I was more or less relaying the message just to see what people thought about the carbs but I need to look at myself. I did look at fuel pump, thats about it.

[Grnx854]

If anyone has one of these sleds I would appreciate if they could snap a picture of there fuel pump and where it's mounted. I would love to do the same but having major pc problems, unless I can figure it out on my phone

[harleysportster]

The 1976 Cyclone round style fuel pump is bolted to the engine base plate under the carb. The 77/78 Cyclone fuel pump was changed to the rectangle style and pop riveted to the inside of the bulk head just under the wiring terminal board. The 77/78 style can be retrofitted and is easier to work on.
As others have stated, change the crank seals. Look up the carb specs and go thru the carb and verify that you have the correct jets. I used to run a '76 Cyclone and it was a strong runner when keep tuned. I would not run the BUE spark plugs, they require a strong cdi system to fire them. Get the standard B10ES non resistor plugs for that fan engine.
As far as quiting once hot, it could be...
crank seals
weak stator
weak coils
worn choke plungers
If you are running a sled that has sat for years, you have to put some maintenance time into it.
Get a service manual.

[jep_800]

This is what I've always seen on the Cyclones. Very simple, as it is a single carb set up, and like Pat said, easy to work on. I was unaware that the 76' came with the round style, so most guys must just switch them out to the rectangle unit.

[Grnx854]

Thanks guys for your input so far. Does anyone know why the links for testing stator and cdi don't work in sum of the threads I found? Or if there's a better place to go for the tests. I have repair manuals and what vintagesnow has but there using a special dealer meter, doesn't give exactly best specs.

[harleysportster]

It seems like Hewtech may have removed his links for diagnosing the CDI. I also need to.update the info I put up in the FAQ section. I no longer have access to the server I was using. I'll try and get the info up later tonight.

[WinnipegStPaul9]

the original pump was a round single pump Mikuni but they've been replaced with the 002-220 rectangular unit. Still available if needed. Here's a picture of the original round style mounted on the 1977 Cyclone that I restored several years ago. This picture of course is prior to restoration.

DA

[harleysportster]

Eric,
If your system has the round plugs, the color code of the wires are the same. You can check everything except the CDI box with an ohm meter. If all components are good, the cdi box is bad.

[jep_800]

I found this online: for Mean Sea Level to 2000 ft above. (I believe central North Dakota is around 1400 - 1500 ft)

Mikuni: VM34-84
Main Jet: 410
Jet Needle: 6FL14-2 (e-clip second position down)
Needle Jet: Q-0
Throttle Valve: 3.0
Pilot Jet: 20
Air Screw: 1 open

Jason

[Grnx854]

Thanks a bunch guys. I will look at more this wknd and get back to you. As far as pictures go I can't get over hem off my dam phone so will reshoot with camera and try again. I did take pics of pump and needle n seat. The needle and seat in other sled that was in question is one I've never seen b4. I looks like a ball bearing wear the needle would go with another smaller ball closer to the seat area. But u can't remove them from the housing/seat because the ends are nurraled. I will try and get pics,sorry. My main pc is down now and older Mac laptop won't let me take my pics off my phone so....unless someone can tell me how I can put pics from my phone on to forum, I don't see attachments spot on bar.

[Grnx854]

[quote="jep_800"]I found this online: for Mean Sea Level to 2000 ft above. (I believe central North Dakota is around 1400 - 1500 ft)

Mikuni: VM34-84
Main Jet: 410
Jet Needle: 6FL14-2 (e-clip second position down)
Needle Jet: Q-0
Throttle Valve: 3.0
Pilot Jet: 20
Air Screw: 1 open

Jason[/quote

That's what there set at, well all but not 100% on pilot jet because can't read numbers but pretty sure.