74-75 Arctic-Cat T7 FIREPLUG CDI

[shewelt]

In my 10+ year quest to design a replacement Fireplug CDI for the ArcTic-Cat T7, I ended up having to purchase a package deal of a 74 340 & 440 El-Tigre.  The 440 is a T7, it has 900 original miles, complete and runs, so half the battle is won.  This will be the test-sled for the CDI development. 

The 340 is a T1 (single plug heads), 290 original miles, but was disassembled for restoration, so some boxes came w/it. 

This weekend starts the CDI development clock ticking.  I'll post progress and at some point, will need a volunteer to verify what I'm finding.   

Here's a pic of the new beauty!

PS:  It goes up for sale as soon as I'm done!!  The Twisters are already talking $hlT about me bringing these things home;)

[Vintagesleds.com]

[Tommcat]

i can test, and dyno, on a 73 El Tigre 440 quad plug or a 75 Z 440 quad plug

[Zed]

Great news. I can test one on our T7 340 race sled when we get some ice on the lakes, warm and wet here now. For sure we will buy one when you have them available.

[shewelt]

The 440 Test sled that i picked up absolutely runs great!  Got very lucky getting such a nice sled that I don't have to work on to get running.

Now my complaints;  If you design a CDI and mount it on an engine that you can't really remove without pulling the engine, the CDI should never fail & be bullet-proof!  What a PITA to get that CDI out of that box on the T7!

Anyway, I have a question for the T7 owners.  The CDI that I removed has 1 mounting bolt per side on a diamond shaped CDI base.  The CDI's that I have on hand have (4) bolt holes (2 per side) so are different.

Does that mean the (4) hole Kokusan CDI is for the T1 engine & not the T7?  Want to be sure this 74-440 has the correct CDI & stator on it before I commit to designing one for it. 

Any help? 

Thanks....Scott

[derwood]

This is the CDI out of a 75 El Tigre. This is what the T7 CDI box's look like.
The CDI out of a T1 only uses 2 bolts to hold them on if I remember correctly.
Derwood

[shewelt]

Thanks for posting.  I have that CDI as a SAMPLE and assumed it was from the T7...which you just confirmed. 

Now the CDI that I pulled out of the Test-Sled doesn't look like that, it look more like a Polaris foorprint, but has all the correct terminals & wire colors for the T7 engine.  So now I'm wondering if somebody switched over the stator & CDI to a T1 system..

Would it fit if they did?

Is this the correct specs for thethe T7 stator?
Here's the spec's I found...

RED to GND = 295-ohms
RED to WHITE 23-ohms


While I'm asking, what would the T1 be in case mine was swapped?

[derwood]

I will get the numbers for you in the morning plus I will get a pic of a T1 CDI box.
Derwood

[shewelt]

 From 2 years ago

https://vintagesleds.com/bs/index.php?topic=353765.0

[shewelt]

OK, more confusion

I just measured the stator in the T7 test-sled. 

RED to GND = 270-ohms
RED to WHITE 4.6-ohms

The CDI is a 2-bolt Kokusan CU11-60-00 with all the correct wire colors and terminals.

So the stator doesn't match the specs for the T7 or T1 that I have. 

Anybody recognize what this stator / CDI is from?  Has to be another Kawasaki model (John-Deere ??)

It's never easy!!! 

[Zed]

The 440 Test sled that i picked up absolutely runs great!  Got very lucky getting such a nice sled that I don't have to work on to get running.

Now my complaints;  If you design a CDI and mount it on an engine that you can't really remove without pulling the engine, the CDI should never fail & be bullet-proof!  What a PITA to get that CDI out of that box on the T7!

Anyway, I have a question for the T7 owners.  The CDI that I removed has 1 mounting bolt per side on a diamond shaped CDI base.  The CDI's that I have on hand have (4) bolt holes (2 per side) so are different.

Does that mean the (4) hole Kokusan CDI is for the T1 engine & not the T7?  Want to be sure this 74-440 has the correct CDI & stator on it before I commit to designing one for it. 

Any help? 

Thanks....Scott

There is no box that the CDI is inside of on any of the T7 engines that I have had and I have owned most of them over the years. The CDI box is stand alone and is mounted on the side of the flywheel housing and is relatively easy to remove with the engine in the sled. All the T7 CDIs are 4 bolt as previously posted, the T1 CDI is 2 bolt and contained in a plastic housing. What you possibly have is the CDI box used on the late 70's Kawasaki T7 engine used in the Kawasaki snowmobiles. I have been told by some that that CDI will work in the Arctic/Kaw T7 engine and the wiring is the same. I had one of those engines but gave it away some years ago.

[Garage Philosopher]

As per the '74 Service school manual, All the A/C breaker boxes have the same number and colors of wires. The main difference of the T-7 units is two secondary coils wired in series...

[derwood]

The 440 Test sled that i picked up absolutely runs great!  Got very lucky getting such a nice sled that I don't have to work on to get running.

Now my complaints;  If you design a CDI and mount it on an engine that you can't really remove without pulling the engine, the CDI should never fail & be bullet-proof!  What a PITA to get that CDI out of that box on the T7!

Anyway, I have a question for the T7 owners.  The CDI that I removed has 1 mounting bolt per side on a diamond shaped CDI base.  The CDI's that I have on hand have (4) bolt holes (2 per side) so are different.

Does that mean the (4) hole Kokusan CDI is for the T1 engine & not the T7?  Want to be sure this 74-440 has the correct CDI & stator on it before I commit to designing one for it. 

Any help? 

Thanks....Scott

There is no box that the CDI is inside of on any of the T7 engines that I have had and I have owned most of them over the years. The CDI box is stand alone and is mounted on the side of the flywheel housing and is relatively easy to remove with the engine in the sled. All the T7 CDIs are 4 bolt as previously posted, the T1 CDI is 2 bolt and contained in a plastic housing. What you possibly have is the CDI box used on the late 70's Kawasaki T7 engine used in the Kawasaki snowmobiles. I have been told by some that that CDI will work in the Arctic/Kaw T7 engine and the wiring is the same. I had one of those engines but gave it away some years ago.

Actually, the 73 El Tigre's CDI was mounted inside a box on the flywheel housing. That's the only year though and it still used the 4 bolt type CDI box.

It looks like though from the previous thread, everything about the boxes is the same other than the Ohm's coming out of the exciter coil, the T1 has 195 ohms and the T7 has 295 ohms. Would that be needed since it runs 2 external coils?
Derwood

[Zed]

Attached are a couple of pics of the Arctic/Kaw CDI box and housing, all the free air T7 engines I have ever seen are the same as this. Please post a pic of the entire engine you have, perhaps we can identify it.

[shewelt]

I do notice my engine bell housing is T7A and only has (2) mounting holes for the Aluminum box with the CDI for mounting. The CDI box cover is plastic, 2 screws (flat-head).

So the crankcase I have on this T7A is different than the T7C you show. See pic.  anyone recognize?

I'll have to try my T7 CDI on this sled and see if it does work. 

This engine runs great with this "unknown" CDI/Stator and I'm seeing a lot of timing movement, more than I expected.  My hope is the T7 box will mirror this existing CDI, so I can move ahead with the development.   I have found the engine starts & runs past mid range with the Fireplug prototype, then falls on it's face, exactly where I left off a year ago when I had a few guys try it.  So hoping I can use what I have to solve it.  Else I'll be in the market for a known T7 stator to put in it (maybe a flywheel too if that ends up also being different) 

Keep replying with whatever you know...I know nothing about Arctic Cat's so absorbing this info as it comes in!  Thanks!

[derwood]

That is a 73 engine or at least the ignition set up is. That is the only year that has that type of CDI box set up. 74 and 75 use the type of set up that Zed shows. The box is the same between the engines though.
Derwood