Polaris Engine - Snowmobile Forum: Your #1 Snowmobile Forum

scuba · 03-10-2008, 07:37 PM

can any one tell me the year and specs for a polaris engine #ec34pm 05. my son bought a 1980 polaris txc 340 but the parts we've been getting don't seem to fit. i thought maybe the engine had been switched. also will a br9es plug be too hot for this fan cooled motor? the previous owner had been running 32:1 mix. i was thinking 40 or even 50:1 would be a better mix. any suggestions? appreciate the help!!!

oldie yungin · 03-11-2008, 03:05 AM

The 40:1 mix would be perfectly okay for that sled.As long as its not an old iron dinosaur than long gone are the days of 20:1 mixing.Also the br9es should be the right heat range plug for it too but personally i use the non-resistor plugs as opposed to the resistors.They're usually easier to find and sometimes cheaper too.As for the engine the only thing i can tell you for sure is its a 340 from the serial# but thats just common sense..the other #s make no sense to me

oldie yungin · 03-11-2008, 03:09 AM

Oh and if you have any doubt than check the fan belt and replace it if necessary and check the crank seal on the clutch side for leaks..those will both leave you stranded and are cheap fixes

**RJ Gleason** · 03-11-2008, 06:16 PM

TXC is a free air engine.
Should have EC34PT-07 in it.
You need to run resister plugs wit the CDI, or you could have problems.(burn it out)
The Br9ES is the correct plug for most of the engines.
The EC34PM01/02 is a fan cooled engine.
I had one of those and it was a nice little sled, quick and agile on the trails.

Got any pictures of it and in the engine compartment?

scuba · 03-11-2008, 06:22 PM

Oldie Youngin - thanks for the heads up. i will check those gaskets although there are no #'s on the fan belt it looks to be in good shape.

scuba · 03-11-2008, 06:30 PM

Old Cat Rider- you are correct with the free air, that is why i was inquireing about the serial #. i just looked at it again and the # that i posted is the one on the engine but i can't seem to find reference to the 05 part of it. i will take some pics and put them on here in the next couple of days. thanks for the info!!

oldie yungin · 03-12-2008, 01:04 AM

I didn't know they made free airs in the 80s i thought that was when everyone was going from fan cooled to liquid.I don't want to bicker about spark plugs but i have a 90 indy 400 and i've used b9es plugs(the non-resistor ones)for about 4 years and 2000 miles in it and have had no trouble yet.my understanding was that the only concern with non-resistor plugs is the rf interference like you would never use them in your car or your radio would be all staticy.

**RJ Gleason** · 03-12-2008, 05:12 AM

Yep, the TXC was built over a two year period and was first a 340 and then a 440.When they changed to the Indy chassis, it became either a liquid or fan cooled.
That was the last of the free air sleds.
It is recommended in all manuals that you use a resistor plug with a CDI, as it will prolong their life.
Over time, the CDI will degrade due to incompatibility from non resistor plugs.

Skligmund · 03-12-2008, 11:44 AM

The 05 is supposed to be a free air model. Was it somehow modded to put a fan on it? You mentioned you looked at the fan belt...

**RJ Gleason** · 03-12-2008, 03:44 PM

The EC34PM are all fan cooled engines. It would appear that the previous owner has done a transplant to resolve a possible blown engine, and the EC34PM 05 is a newer engine version.

scuba · 03-12-2008, 08:04 PM

here are the pics from the '80 txc. although you can't make out the serial # very well and you can't see the 05 part at all. i will post the first 5 then the rest.

scuba · 03-12-2008, 08:08 PM

here are the rest of my pics. my '86 pantera is also in there.

scuba · 03-12-2008, 08:14 PM

if you go back to my original post the main part of the story is there. i believe the original owner replaced the engine. i just couldn't find any engine #'s with the 05 part. the only referance to the engine # is the ec34pm 01/02 models which were fan cooled and the ec34pt 07 that was free air.

scuba · 03-12-2008, 08:16 PM

could the 05 possibly make it an indy engine?

**RJ Gleason** · 03-12-2008, 11:59 PM

Definitely not the original engine.
It probably is from a much newer sled though as the manual that I have for oder sleds does not list that engine at all.

scuba · 03-13-2008, 09:49 AM

i can't seem to find any info on it either. sure makes it hard to get parts that way. thanks for the help though!!

Skligmund · 03-13-2008, 11:36 AM

Well, this site I have linked seems to have a fairly complete listing of engines, and I don't see a -05 variant. Are you SURE that it read -05? It doesn't show in the picture.

polaris snowmobile gaskets

Also, I thought the cutout in the front of the sled looked abnormal or a fan cooler. The 79 TXC came with an ECPT-05 and the 80 model came with a -07. Both free air.

oldie yungin · 03-13-2008, 11:58 AM

So i was right after all...Someone shoe horned a fan cooled indy engine in a free air? Sounds like a minnesota redneck jobber to me.I would like to hear other peoples opinions on the whole resistor plug thing.Being a mechanic i see bulletins and recommendations in owners manuals every day. If everyone followed what was in their owners manual there would be no need for parts stores or aftermarket parts because everyone would be at the dealer getting service with oem parts only. Not the case though is it?

palmrose2 · 03-16-2008, 05:25 PM

EC34PM according to my info were used from 1977 to 1981. All ran a 40 to 1 oil mix. All had points, no CD ignition. Prior to 1981 they call for br8es. 1981 is br9es. Gap is .020". They have no fan belt. I don't think ANY Fugi engine ever had a fan belt.

Polaris used these engines in Colts, SS340s, Apollos, Cobras, and the Cutlass.

I have some tuneup info if interested but it would be nice to know really for sure about the -05 or whatever number. I don't see the engine in my manuals.

palmrose2 · 03-16-2008, 05:33 PM

[quote=oldie yungin]I would like to hear other peoples opinions on the whole resistor plug thing.

Non resistors are fine as long as you stay away from peoples homes and vehicles. They can cause interference even away from the vehicle they are used on. Usually have to be fairly close for it to really bug people.