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Savage 25 starting issue.

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stickerbloke

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Hi all I'm new to all this car lark so plesae be gentle with me.

Bought a 2nd hand Savage 25. Fantastic bit of kit me and my 7 yr old love it. Managed to get half a tank of fuel use out of it before it cut out and would not restart. Ill list what happened.
1. Running fine noticed fuel was low so brought it close and refuelled

2. Truck moved off then and started to kind of loose performance so was driving it back to me and it cut out.

3. Tried to restart with that moto start thing but sounded like no compression.

4. Took out glow plug and tested, this was fine.

5. Blew down the fuel line to eliminate air locks

6. Took the Glow Plug out and turned it over the piston looked like it was not moving.

Thats as far as I have got not really knowing these things I have not wanted to do too much as I dont want to cause any more damage. Any help would be greatfully received as I have a 7 yr old thats not a happy bunny lol.

Thanks in advance

Andy D
 
Could have snapped the shaft or the connecting rod, but if you don't see movement of the piston you've got either failure of the roto-start mechanism or a failure in the rotating assembly of the engine. I'd highly suggest taking it to someone before attempting home repairs. These things require super accurate machining. Don't be surprised if you find out it's irreparable and needing replacement.

I'm guessing you're in England, probably SW? If the day you were running it just happens to be one of those freakish days that the sun comes out, it could have leaned out and ceased itself. Remember, air is less dense when hot and your engine will feel the slightest change.

I'd suggest purchasing an infrared heat gun, you can pick them up for a few quid probably at Homebase or something. You need to keep a close eye on your exhaust gas temperature, and your cylinder head temperature. You should be able to find the temperature requirements by googling the engine type (I'm new, so I don't know) and adjust the carburetor accordingly.

Understand that my knowledge is not of RC's, it's just applied automotive/mechanical knowledge. With that in mind please do verify all that I'm saying, and correct me if I'm wrong. I don't believe I've steered you wrong but you never know.
 
the only way you are going to learn your own buggy is to have the parts diagram out and open her up and see whats going on just take your time and be carefull!!! your owb could be done for. which would be an easy fix,, ummm I would start at the one way bearing to see if that is still doing its job, and then I would open the engine up to make sure everything iis good in there and then you can take that opertunity to seal up the engine when it goes back together because you will have even better luck with a sealed engine, because you wont get any air leaks, or moisture in it.. I havent worked on a savage before but about the same principles.. good luck and I am sure a savage owner will chime in as soon as they notice your post.. good luck!!!
 
When you turn it over with the rotostart do you see the flywheel turning too? If so, the crank is in one piece. You may have broken the connecting rod, or it might be a bad rotostart gear in the back plate or the one-way bearing.

I agree, if you don't have the full exploded view manual, download it from HPI (they have a great UK site BTW) and take a look yourself. That's the only way you'll learn. I'd start by pulling the backplate off (only four screws) and checking the gears and OWB before going into the engine itself.

And another agreement on the temp gun. Or at the very least Google nitro spit test and learn how to check the temp by dropping a little bit of spit on the cooling head of the engine.

Good luck and report back what you find!

Mark
 
Ill have a look today. Hey really appreciate your help with this hopefully ill pick up some new skills and return the favour
 
Is there any site that I can get a picture or diagram where exactly to be looking for the owb etc ??? Sorry like I said really new to all of this car stuff but really eager to learn and want to try and do things myself I find that more satisfying than throwing money to someone to do it for me, kinda takes the fun out of it all :-)
 
Oh excellent thanks for that ill go look now and give a progress report later. Got a 7 yr old pestering me lol
 
Right undid the rear safety bumper and pulled the protective cover thats attached to the chassis. I think the drive shaft that connects the back wheels to the engine fell out when I was undoing everything. Now I put that back in and enclosed a picture of underneath the rear wishbones. Now is this the part I have to remove to look at the OWB the cog thing in the middle (sorry dont know technical word)

2011-07-15160118.webp


---------- Post added at 10:32 AM ---------- Previous post was at 10:06 AM ----------

Right sorry about the updates just adding things as I do them. I put the roto start rod into the back and turned manually by hand. Now there felt no compression and from what I could see nothing else was moving when I turned it. Is there a test I can do or something or should there be anything visable moving. Trying to give as much info to the gurus amongst you that might help me out :-)
 
Umm,no that's differential you have in the above pic.The owb is under the plate where you put the roto start wand in to turn it. If turning the the roto start doesn't turn the engine over,your owb needs some attention,cleaning or replacement. You can try cleaning it with denatured alcohol,that fixes a lot of them but they will wear out and need replacement from time to time too.
 
Right cheers ill look now lol. Told you I was a nooob. Now PS3 and Black Ops I'm ok with lol

---------- Post added at 1:24 PM ---------- Previous post was at 12:58 PM ----------

All apart. Looking at the bearing it does seem to have a lot of greese on it but looks like its turning the shaft like it should, i.e grabs the shaft in one direction only. If I take the glow plug out and turn that shaft would I see the piston moving up and down through the hole where the plug was ?
 
Right sounds like a replacement engine then as I'm turning the shaft and piston is not moving
 
Hi again :-) Thanks for the replies these really are helping me no end. I know my truck is probably shafted but I'm enjoting the process of learning whats wrong. I'm unsure what the flywheel is I have enclosed another picture. Is it the silver wheel just under the Carb. If it is that will spin round in one direction it feels like it grabs every now and again but will not spin round the other way. I have ordered a one way bearing just in case.

Also When the rotostart plate was off I tried to take the plate off the engine that the shaft was in. This was unsucessful as one of the small allen keys had been rounded off looks like someone has been at it before.

2011-07-16103551.webp


2011-07-16103551.webp
 
Yes, that's the flywheel. That should turn when you spin the engine with the rotostart or the OWB...

If the flywheel turns OK one way but jambs up the other way I'm fairly certain your rod is busted. Take the glow plug out and turn the flywheel with your fingers. If the piston doesn't move the rod is busted...

Mark
 
Yes no movement of the piston. I take it to remove the rod I need to remove the back plate off the engine, the one just behind the one way bearing ?
 
Oh dear here is the problem. Looks like it has siezed and snapped the crank shaft. Bit of work ahead now lol. Is that due to running to lean on a warm day ???

2011-07-16152840.webp
 
Ouch! Sorry to see you found the problem! LOL

Internal damage could be from many issue. Running lean, too much rpm, excessive wear, poor maintenance, etc.

If you're on a budget you can get a new crank/rod/piston/sleeve in a rebuild kit. Next cheapest would be HPI's engine exchange program. Otherwise it's time to go engine shopping...

Mark
 
Just bought a brand new one but got external damage bent fins and dented casing in places its a pull start but I can put the rotostart on the back can't I instead ? Got it for £35 posted got to be a bargain :-)
 

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