ZR.32 Spec.4 engine in a Hpi savage 21?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
What you have is just the starter housing. You don't have a backplate. The housing has a top half and bottom half. The 4 holes on the starter match to a pull start type backplate, which has 4 holes to bolt it to the crank case and 4 more holes to bolt the starter too.

Like this:
lrp38557.jpg
 
I see now. Nice pic. so if i get a backplate for this particular engine it may fit. Which i need anyway. Thanks for that.
 
Cant find a backplate available anywere. Need the one-way bearing too, but that one i found on eBay. Anyone know where to find one or a similar backplate that Will fit? ?
 
That rotostart will fit once you get the sh pull start back plate
The rotostsrt uses outer holes on the backplate and the backplate used the inner holes
 

Attachments

  • B111C591-DF52-4F14-A81F-1A83A9C41DE4.jpeg
    B111C591-DF52-4F14-A81F-1A83A9C41DE4.jpeg
    39.3 KB · Views: 2
Hi again folks. Ive recieved the sh backplate today but when i was on my way mounting it together i noticed, that theres no way that this is all i need. Still parts missing. Posting pictures. Please point me in the right direction. 20190914_222817.jpg20190914_223221.jpg20190914_223221.jpg20190914_223154.jpg20190914_222954.jpg20190914_222938.jpg20190914_222832.jpg20190914_222829.jpg20190914_222824.jpg20190914_222817.jpg
 
One way bearing: https://www.amazon.com/Redcat-Racing-h025-Sh-28-Bearing/dp/B002YV5SQO
Starter shaft: https://www.amazon.com/Redcat-Racing-Pull-Start-Shaft/dp/B002YV9NNI

Usually also a pen spring in the center of the starter shaft that presses against the housing that keeps the starter shaft pushed into the engine. You can see it in the photo here:
https://www.hobbytown.com/sh-engines-.28-pull-starter-front-parts-set-shets3a-1/p524272

I don't know if roto starts need that or not. I've only had pull-starts and the ones with the OWB inside the engine with a starter shaft like that have always had a spring.

I don't know if either of those will fit your stuff though. Was just posting examples of what remains. You may also need a gasket for the back plate. I don't know what came with yours.
 
One way bearing: https://www.amazon.com/Redcat-Racing-h025-Sh-28-Bearing/dp/B002YV5SQO
Starter shaft: https://www.amazon.com/Redcat-Racing-Pull-Start-Shaft/dp/B002YV9NNI

Usually also a pen spring in the center of the starter shaft that presses against the housing that keeps the starter shaft pushed into the engine. You can see it in the photo here:
https://www.hobbytown.com/sh-engines-.28-pull-starter-front-parts-set-shets3a-1/p524272

I don't know if roto starts need that or not. I've only had pull-starts and the ones with the OWB inside the engine with a starter shaft like that have always had a spring.

I don't know if either of those will fit your stuff though. Was just posting examples of what remains. You may also need a gasket for the back plate. I don't know what came with yours.
Thanks! I was told that no spring is needed but i need to purchase the other parts.
 
Pics.
 

Attachments

  • 20200404_073444.jpg
    20200404_073444.jpg
    235.3 KB · Views: 3
  • 20200404_073436.jpg
    20200404_073436.jpg
    239.8 KB · Views: 3
  • 20200404_073421.jpg
    20200404_073421.jpg
    188.3 KB · Views: 2
  • 20200404_073417.jpg
    20200404_073417.jpg
    177.6 KB · Views: 2
  • 20200404_073351.jpg
    20200404_073351.jpg
    290.5 KB · Views: 2
  • 20200403_052514.jpg
    20200403_052514.jpg
    259 KB · Views: 3
  • 20200402_052931.jpg
    20200402_052931.jpg
    303.5 KB · Views: 3
  • 20200403_052507.jpg
    20200403_052507.jpg
    190.7 KB · Views: 2
One other problem I came across was when using a roto start & HPI wheelie bar the stock wand is to short to reach onto back plate, had to pay over the top & get the HPI XL 225mm one sent from France as RC shops in England were saying it would be months before even getting close to be able to give me a delivery date for it!
From the beginning way back of using a roto start I had to grind a groove in centre of shock tower to be able to get roto wand more horizontal to then not engage at such a steep angle!
 
Pics
 

Attachments

  • 20200405_071159.jpg
    20200405_071159.jpg
    244.3 KB · Views: 3
  • 20200405_071204.jpg
    20200405_071204.jpg
    218.3 KB · Views: 4
  • 20200405_071208.jpg
    20200405_071208.jpg
    251.5 KB · Views: 4
  • 20200405_071217.jpg
    20200405_071217.jpg
    234.9 KB · Views: 4
  • 20200405_072426.jpg
    20200405_072426.jpg
    181.1 KB · Views: 4
  • 20200405_072433.jpg
    20200405_072433.jpg
    218.5 KB · Views: 4
  • 20200405_072439.jpg
    20200405_072439.jpg
    333.2 KB · Views: 4
  • 20200405_072447.jpg
    20200405_072447.jpg
    254.8 KB · Views: 5
  • 20200405_072513.jpg
    20200405_072513.jpg
    281.3 KB · Views: 4
Pics
 

Attachments

  • 20200408_052752.jpg
    20200408_052752.jpg
    272.4 KB · Views: 5
  • 20200408_052802.jpg
    20200408_052802.jpg
    217.1 KB · Views: 5
  • 20200407_051409.jpg
    20200407_051409.jpg
    236.6 KB · Views: 5
  • 20200407_051414.jpg
    20200407_051414.jpg
    234.1 KB · Views: 6
  • 20200408_052747.jpg
    20200408_052747.jpg
    289.6 KB · Views: 6
  • 20200409_074706.jpg
    20200409_074706.jpg
    394.1 KB · Views: 6
  • 20200410_064137.jpg
    20200410_064137.jpg
    288.4 KB · Views: 6
  • 20200410_064142.jpg
    20200410_064142.jpg
    388.7 KB · Views: 6
This was a first startup run with rotostart in the back. Works like a charm, as you can see in one picture above, the dock to the wand is in center of chock Tower. I don't know how it works with wheelie bar, haven't mounted that one get.
 
The first problem i encountered was that when it runs at idle and i push the throttle the engine dies. When i start it again it fires right up and runs at idle like in the clip i posted. All settings are at factory settings. The other problem is the amount of fuel leaking out of the exhaust tip. Theres not much smoke either.
 
Actually, now i cant get it running at all. Its so rich on fuel, that its goes into hydrolock emedaiatlly. The startmotor its not powerful enough. Yes, it worked yesterday when its started easy. Now, nothing. It has already destroeyed a New glowplug. The glowplug is died. Can the glowplug stop working completly because of to much fuel?
 
Factory settings are just a guide. I would try leaning the hsn. Glow plugs don't like too rich or too lean. Loosen the glow plug a bit to ease starting but retighten. Breakin methods vary but try get temps to 200F.
 
Yesterday when i started it for the first time, i didnt Touch the needles. And it run. Now, i reset the needles to factory and it wont start. My guess is that the factory settings wont work for this engine. I Think it was 5,5 turns lsn, 5. 3/4 turns hsn. Does anyone have settings the know work for my engine?
 
Try 1/8 turn clockwise on hsn. It will be trial and error as conditions and engines vary. It's a new engine so you want richer settings for break in. Get it going then drive slowly in figure 8 for a few tanks, then start leaning more. Glow plug can be loosened just a 1/4 turn to reduce compression, but retighten before driving, yes it will leak but overcomes really tight pinch on new engine. Try raising idle rpm using transmitter throttle adjuster as it has less power when rich. Make sure glow starter battery is fully charged and glow plug glows really bright. Nitro can sometimes be frustrating so take a break and come back later after a bit of distraction. If it gets flooded and wont turn over then remove plug, tip it on its side and crank over to get fuel out. If you haven't then take air filter off and check idle gap is about 1mm.
 
Thanks! Yes, the gap is 1mm when insert is removed. This are the settings i use now.
 

Attachments

  • 20200411_112937.jpg
    20200411_112937.jpg
    186 KB · Views: 4
Like all had said above it’s a trail & error exercise, but try one thing at a time & keep going with it several times until you go onto trying something else otherwise your go round in circles not remembering what you tried/adjusted if you adjust/temper with different settings all at once! ??
 
Got it running, but no idle. Have to give it a little throttle. As soon as i let go, it dies. Very high compression. Have to release glowplug before start attempt. Then the gear of the backplate to the rotostart Signed out. Brand New. Bad quality? I tried rotate engine by hand and thats no problem but the gearing for backplate is shut to pieces. Which is the easiest way, changing it? Taking of the shocktower in the back and this way, leave the engine in place?
 
Best remove engine to remove backplate. Usually its the smaller gear that breaks its teeth, which happened to me on a cheap chinese roto backplate.
 

Latest posts

Members online

Back
Top