Polini Thor 303 Rebuild (How to)
Vložit
- čas přidán 25. 08. 2024
- The replacement parts arrived for the Polini Thor 303 rebuild. Dave and I made the 3 hour round trip to Cloudbase Ppg where London Ivey demonstrated a proper rebuild. Even though I still have a bad taste in my mouth over the whole deal and how Polini handled it, 'm over all of the negativity. London is my importer for Hscom trikes and Polini. Let me be clear here he has been on top of his customer service game from day 1. When my first engine overheated he showed up within 2 days and installed another new engine out of his own pocket. He has been in constant communication with me and went to bat every chance he had. These importers are expected to be 2 stroke experts with little or no guidance from the manufacturer. I'm lucky to have him and his many years of experience to learn from.
I honestly hope that this is the fix for these engines for the sake of all the people from all over the world that purchased them. I hope this video can help some of the people who don't have a mentor like London nearby to guide them. If you have any questions of issues reach out to me. If I don't know the answer I will find it for you.
I will install my 303 on a trike in the coming week and start the break in process over. I'll keep you all updated here on the channel. I am a dealer for Hscom Trikes find links to my school and Londons operation below.
Florida Flight Sports
ppggorilla.com/
Cloudbase Ppg
www.cloudbasep...
I hope the new parts resolve the issue.
I worked in After Sales for more than 25 years (so called "premium"-brand...) and also had to decide on warranty claims.
My principle: in doubt we accepted warranty claims - this helps to build up a strong bond to a customer.
Looking forward to see how it hold up.
Nice! You beat me to it. Now I can watch your video first ! 👍😎👍
Did yours burn up too?
@@PPGGORILLA No, its brand new. Still dry. But they shipped me the fix-kit already.
@@Chris-Fennimore lololoololool. An engine that ships with a fix kit. What is included in the fix-kit? I've never heard of this. I never deal with new engines or ppgs though.
@@Chris-Fennimore Okay, yours will be easy then!
@@Chris-Fennimore Nice - sounds like Polini is staying on top of this issue. Took a little bad publicity to do so, though!
Well done!
First of all, you don't have a Compression issue you have a Jetting problem. Since it looks to be fairly New, I wouldn't suspect Case Seals or Carb Boot Leaking.
Detonation usually eats around the Piston edges or just breaks a Piston.
Polini's have problems, short Life Span, account they use to High of rpm. Industry Standard is Max 6500rpm.
Go Carts, Snowmobiles, Bikes, Speed up, Slow Down, Speed up, Slow Down, Stop, on and on! Airplanes turn at continuous RPMs!
Even though these are Water Cooled they don't have a Big enough Radiator to Cool them at that High rpm.
Polini 303 (Water Cooled)
38 HP at 8000rpm
(76mm x 62mm)281.37cc
11.2:1 cr to say 9.5cr = 1.7hp loss.
Dell’Orto VHST 28mm Carb.
Great vid, Rick! Right up my alley. Glad Polini finally came through for you. Hard to tell on camera, but it looks like they machined the head squish area back a bit (making it a thinner area), increasing the volume in the center around the plug. At the same time they must've milled the head down a few thousandths, otherwise they wouldn't require that spacer under the plug. The piston must be capable of hitting the plug with the new head. Interesting way of doing it. Tucker said on his Instagram that the power deliver is VERY smooth with the new parts - guess it tamed it down a bit, which we all expected. Doesn't have the sharp hit that it had before. Now it's just power everywhere.
Just like my old dirtbikes! Brought back a lot of nostalgia for me. I rebuilt a '87 CR125R in my basement when I was 17. Same deal except I had the 6-speed transmission, clutch, and a power valve to deal with. Then I had a '88 Honda TRX250R Fourtrax in my early 20's - that thing was an animal! Peaky and explosive powerband. There wasn't a hill in any sand pit that I couldn't climb! When I rode on the street, the front end would come up 2' with every single gear! So much fun! That sport has pretty much been outlawed up here, so paramotors are my new hobby. :)
I couldn't imagine working just about outdoors like that this time of year! You guys are so lucky! It hit 57° up here for a minute, along with 50 MPH winds that blew one of my metal sheds across the lawn. Destroyed. Now it's 25° again. :(
Yeah I'm excited to get it mounted back up so I can fly it and feel the difference. I'm sure loving the Cosmos though. Still trying to find time to get the break in flown off of it. I need my #1 mechanic Smitty down here to help me test these engines out!
@@PPGGORILLA - If my wife gave the green light, I'd start packing right now, brother! I miss you guys and that climate!
I just saw that I missed your Cosmos video. Sounds like that's a great setup. Going to watch the vid now. 👍
Need to send that 303 to Texas for testing ;) 😂
You got it Brother!!! Send a check!😜
What an excellent video Rick.. always wanted a Polini, this vid may give me some comfort that will happen someday
Zeus is always good company. 👍
That's a nice engine. I have aquarium pumps made in Italy and they make good quality stuff. I like that a lot of their stuff is reparable.
Yeah, they run very reliable for about 10-20 hours. lolololol
@@Agustin-jo8mv Well Italian aquarium pumps work for many years reliably. I don't know much about these engines.
@@JonVlogs123 got ya. PPG Gorilla mentioned they hadn't accounted for the fuel type here in the US, more specifically Florida, which is what caused that engine to fail very quickly.
@@Agustin-jo8mv oh ok, that makes sense.
Good job Rick this will help those unfortunate enough to have bought one of these ....things.
I really hope you don't have any more issues with that engine!
I hope the head and needle fixes the issue.
I have a Thor 190 Light which gave me 2 piston holes while I was using AvGas so it was definitely not an octane issue.
Fresh Breeze ended up replacing the entire ignition system after almost all of them in the field failed with piston holes.
Polini later came out with an "HF" kit - which included a spark plug heat sing, a new head to fit the heat sink, and a new cooling shroud.
100 hrs later I'm still basically satisfied with the engine.
If your Burning Holes in the middle of the Piston #1 it's a Jetting Issue, #2 Case Seals, #3 Carb Boot Leaking.
Did he have to take back off the head........to reinstall that upper motor mount bracket? Enjoyed the rebuild!
Good vid
Yep --that piston hole was the same as my friends engine.
Sure are a lot of things to an ICE -- shows how simple electric motors are in comparison -- come on better batteries!!!
I think this fix will now make this engine the cats ass 🤞
Safe landings
Thanks Patrick. I'm excited to put this through the paces now. I hope it fixes it perminantly
Jak długo polatałeś po tym remoncie??? Silnik trzeba było rozebrać. Płukanie nie do końca wyczyści wszystkie opiłki. Też tak miałem.
Thanks you, and the guys that did the rebuild for making this video. One question...What in the heck does that washer under the spark plug do? I've never heard of such a thing. So does the plug have enough threads to hold it in the head? So it raises the plug...looks like 4mm or so. Seems like this would help decrease the compression, and put the spark further away from the top of the piston. Maybe they just want the hot spark further away...less heat? Are you sure they really modified the head? Looks the same except for the top where Polini made room for the "washer". I submit, now I could be way off base, but I think they took the old head, kept the the combustion chamber the same and just moved the tip of the spark plug away from he top of the piston by 4mm.
I read the new specs somewhere but I didn't take the time to measure it. I'll be happy if it runs dependably.
It does lower the compression. Top 80 old heads used the same thing. They offered a 2mm and a 3mm spacer. New head used a smaller plug and spacer not needed for the top 80.
@@dr420nrg That's interesting...I didn't know that. I wonder if you could use it on any motor (eg. the 250) to perhaps low the compression on that motor.
@@stone8597 don't see why u couldn't. For like lower octane it may help. Would consult with polini.
@@dr420nrg I might do that on my "Black" 250. However, Polini probably will not respond to my question.
Hey just curious, are you using 100LL or high octane (91-93 (R+M)/2) non-ethanol mogas? I’m planning on getting non-ethanol 93 octane mogas, and when only lower octane non-ethanol mogas is available, I’m going to use an octane booster, probably Rislone 4747 or Lucas Oil 10026 which should bring a lower octane gas up by 2-3 octane (called 20-30 points). My goal is to fly no lower than 93 mogas non-ethanol. I don’t want to mess with 100LL and Decalin and lead fouling.
I’ve learned that octane is not about power, it is how hot or cool and how fast or slowly the ignition occurs. I believe both the 202 and 303 are higher compression than the Vittorazi Moster 185 (please check this statement though) and thus will run better and less likely to burn piston holes.
Thanks for posting this tear down and rebuild!!! There is not a ton of motor maintenance videos on CZcams on the Thor 202 and 303. I really appreciate it! I’ll be a Thor 202 owner soon.
I ran only 93 octane ethanol free (US) in this engine. Technically I was within what Polini recommended. I haven't heard of these problems in the 202.
@@PPGGORILLA Excellent feedback, thanks mate! I know another 303 pilot recently also earned a cylinder hole, and he was using 100LL and Decalin. Hopefully the new cylinder design from Polini fixes the 303 issues, and I'm hopeful that US 93 octane non-ethanol gas won't cause issues. Cheers! I'm watching your experience closely, so please keep on sharing, both the good and the bad. Polini has the potential to be great engines, as long as the reliability issues are resolved.
I know that everyone goes back to the Moster 185, which is more forgiving IMO with different gas and oil ratios, which may be why it is more reliable. It may just be that the Polini motors need more babying than the Moster 185 does. Worth it if the 400-hour between major overhaul and fuel efficiency and more thrust hold true. Cheers!
What jet are you running and what clip on the new needle?
116 jet 3rd clip
Smart carb fuel systems adjustable carb will fix all these issues.
Here's a crazy idea Polini - separate profit from reliability instead of sending out ridiculous fixes. I get in my car and go 300k just changing the oil.
I just saw a head washer go on backwards… Don’t mind me… It’s just my OCD… 🧐🤪
wow, they're just modifying old cylinder heads and by the look of that washer they had modified it a lot, I wonder what the stats are now, lower compression =lower power=less hp, less thrust maybe, unless they compensated with cylinder and piston sizes,I still missing out the washer would make the plug hit the piston unless the stroke has changed, looking at the pistons by side I doubt it, I think it's just a case of the spark plug burning up if you left the washer out, not an ideal situation considering the cost
So is the 202 any better? Not a lot of options if you want to go with the Cosmos. I was originally leaning toward the 303. Having to get avgas for it and the 202 really have me rethinking using either of them. I don't want the Moster as I really want liquid cooling.
Yep, I see the problem.. ain't got no gas in it.. 🤣🤣🤣🚮
Did tucker get the same parts.for free 303 😀
Hats off to Dave Curry
Might have a few more PPG pilots coming your way
Yes he has updated his before it burnt up.
you skipped removing the piston!?!?wft
Why the fuck would anyone buy this engine if it needs Av fuel and all this extra bullshit to deal with.
Exactly.... Getting rid of it was a good thing. The guy who bought it is a former student of mine. He flies it a lot and has had no problems using avgas.
Why wouldn't you run the best fuel that you can in an aircraft? It's only your life. I don't even run 93 in my dirt bike or weed eater. I'm not surprised by the result of running low octane fuel in a high compression 2 stroke...detonation. This actually speaks volumes about Polini and there customer service.