J’s dirty 30

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
i'm curious as well, did they use there own carb or your carb when they checked the engine ran ?

just read through the whole thread and and couldnt see anyone mention how far open the butterfly is when you're trying to start the engine,
have you tried adjusting the idle screw in at all,
leave the low and high needles at stock/base settings and wind the idle screw in a quarter turn and try and start the engine,
then another quarter maybe just untill it starts and idles then go from there with the low and high,
don't wind the idle screw in all the way, just a bit at a time and then try and start it as normal,
do it with wheels off the ground or no wheels fitted in case it decides to go super high on the idle etc,
just a suggestion to at least get it started and running at idle (y)
 
Just curious what did the they do to check that the engine ran right? Did they put it in something that can put the engine under load?
They just said it needed tuned, ran rough initially but runs great now. I haven’t seen any replies. I did ask if it ran longer than the 5-10 minute mark where I see a sudden change of how it runs and they replied “yes”.
i'm curious as well, did they use there own carb or your carb when they checked the engine ran ?

just read through the whole thread and and couldnt see anyone mention how far open the butterfly is when you're trying to start the engine,
have you tried adjusting the idle screw in at all,
leave the low and high needles at stock/base settings and wind the idle screw in a quarter turn and try and start the engine,
then another quarter maybe just untill it starts and idles then go from there with the low and high,
don't wind the idle screw in all the way, just a bit at a time and then try and start it as normal,
do it with wheels off the ground or no wheels fitted in case it decides to go super high on the idle etc,
just a suggestion to at least get it started and running at idle (y)
I don’t know if they used the new carb they had sent to me, which I sent back with the engine or their own carb.
Sometimes I go wide open, sometimes I just do a little throttle all with the transmitter.
I have been leaving the needles alone as they were sent to me adjusting the idle screw as you are suggesting. My pull start is feeling like it slips so I may not have a chance to try starting it today. At this point I just want a refund.
Looks like it only lost a half lb of pressure overnight, I don’t have a hand vac anymore so I can’t really test vacuum.
 
Ypu need to get a cheap hand vac/presser tested. I'm partial to mity-vac but you can get cheaper ones off Amazon or harbor freight. The engine should slow be gently rotated while doing the tests. This does a few things, one, it makes sure you didn't inadvertently block a port not allowing pressure or vacuum to get to the entire engine and 2 it will better help to show if the crank seals leak.
Carbs can be tuned closely at different areas, but seldom preform well with any major temp or elevation changes. The settings they had may not be quite right for your running conditions. In these cases it's just best to start over and go through the normal motions of carb tuning. Set the idle stop screw in further then you think you'll need it. Base setting on high and low jet needles. Just get it to idle and let it warm up, set the low jet. Get the idle set right, recheck the low jet, then go for the main jet. You may need to make some small adjustments to the low jet again once the main jet is set, however it should just be a slight adjustment.
 
2 things here:
#1- it started, I had to open the throttle quite a ways, so that tells me there is PLENTY of fuel -
#2- I may be battling a dynamite kill switch issue now, where before, it was working. I got it to idle on a stand and warm up, I hit the kill switch on my tx and it didn’t stop -the kill switch wasn’t plugged in. After plugging it in the engine wouldn’t start and at the same time the pull starter is not grabbing the flywheel.
SO CLOSE
Ypu need to get a cheap hand vac/presser tested. I'm partial to mity-vac but you can get cheaper ones off Amazon or harbor freight. The engine should slow be gently rotated while doing the tests. This does a few things, one, it makes sure you didn't inadvertently block a port not allowing pressure or vacuum to get to the entire engine and 2 it will better help to show if the crank seals leak.
Carbs can be tuned closely at different areas, but seldom preform well with any major temp or elevation changes. The settings they had may not be quite right for your running conditions. In these cases it's just best to start over and go through the normal motions of carb tuning. Set the idle stop screw in further then you think you'll need it. Base setting on high and low jet needles. Just get it to idle and let it warm up, set the low jet. Get the idle set right, recheck the low jet, then go for the main jet. You may need to make some small adjustments to the low jet again once the main jet is set, however it should just be a slight adjustment.
Thanks for the advice. My harbor freight hand vac finally took a chit on me.
I am in Idaho at about 4,000 ft in elevation, it’s not exactly the same as NY where the fearlessRC address is, so I know it’s going to be rich. It honestly seems pig rich on base settings.
 
Something is wrong with the kill switch, unplugged it runs, plugged in, the engine will not run. I messed around with the settings in my tx but couldn’t fix it.
I drove it briefly and while making some adjustments to bring the idle down it died and I couldn’t get it started because the pull starter is slipping off the flywheel.
At least it runs, im just not too satisfied with how much the idle screw is in. If I go leaner on the low and back off the idle screw, it gives me that ‘too lean’ lag from a stop. I was trying to achieve the smallest idle gap possible, but I will settle for where it’s at right now until I can properly tune it.
 
So.
It would appear there was nothing wrong with the engine all the time , carb issues and now a faulty remote kill switch.
I have 2 of these engines and never had the starting issues you describe with them .
Had lots of fun trying to start my scz engine though , could not get it to run on the OBR racing carb I had fitted , had to fit my old Walbro carb with choke , then it fired right up , was flooding like you described on your engine . running well now and leaning off the settings as it beds in.
I would go for an easy start set up on yours , so much better.

car8.webp
 
So.
It would appear there was nothing wrong with the engine all the time , carb issues and now a faulty remote kill switch.
I have 2 of these engines and never had the starting issues you describe with them .
Had lots of fun trying to start my scz engine though , could not get it to run on the OBR racing carb I had fitted , had to fit my old Walbro carb with choke , then it fired right up , was flooding like you described on your engine . running well now and leaning off the settings as it beds in.
I would go for an easy start set up on yours , so much better.

View attachment 93987
A little bit of user error and equipment malfunctions yes, but…. the engine did have some leaky seals initially, it would run great for like 5 minutes then just start stumbling around. Then it would sometimes start, sometimes not. Seemed to flood a lot. If you are new to small engines this can be so confusing.
After I resealed the case and pressure tested it, well it runs good now.
I did not realize my kill switch was at fault, and that was before I sorted the gaskets out.
Now my pull start isn’t engaging the flywheel, I fixed it last night, there’s a wheel or something that pushes out to grab the flywheel and it’s just not doing that. Like it’s catching on the rope reel piece instead of sliding up off of it.
This is hard for me to explain but if you know what that pull starter is supposed to do then maybe you can picture it.
I’m using the Taylor 35 pull starter. For $25 it’s a lot better than the one that comes with these engines.
 
2 things here:
#1- it started, I had to open the throttle quite a ways, so that tells me there is PLENTY of fuel -
#2- I may be battling a dynamite kill switch issue now, where before, it was working. I got it to idle on a stand and warm up, I hit the kill switch on my tx and it didn’t stop -the kill switch wasn’t plugged in. After plugging it in the engine wouldn’t start and at the same time the pull starter is not grabbing the flywheel.
SO CLOSE

Thanks for the advice. My harbor freight hand vac finally took a chit on me.
I am in Idaho at about 4,000 ft in elevation, it’s not exactly the same as NY where the fearlessRC address is, so I know it’s going to be rich. It honestly seems pig rich on base settings.
That's enough to throw it off a decent amount on carb settings, depending on where in NY they are located. Base settings are just that, a point where the engine should run and tune from there. May be rich, or may be lean. The idle screw/throttle plate opening will, also, be different for different areas. There's no set it to 0.025" and call it a day. You get it to hit the idle rpm and get a good transition from low jet to high and call it good.
 
That's enough to throw it off a decent amount on carb settings, depending on where in NY they are located. Base settings are just that, a point where the engine should run and tune from there. May be rich, or may be lean. The idle screw/throttle plate opening will, also, be different for different areas. There's no set it to 0.025" and call it a day. You get it to hit the idle rpm and get a good transition from low jet to high and call it good.
Well I’m here to learn as well as have fun. Thanks for this piece of advice.
 
So.
It would appear there was nothing wrong with the engine all the time , carb issues and now a faulty remote kill switch.
I have 2 of these engines and never had the starting issues you describe with them .
Had lots of fun trying to start my scz engine though , could not get it to run on the OBR racing carb I had fitted , had to fit my old Walbro carb with choke , then it fired right up , was flooding like you described on your engine . running well now and leaning off the settings as it beds in.
I would go for an easy start set up on yours , so much better.

View attachment 93987
What exactly needs to be done to fit an easy start on a 30degree engine? It looks like some come with a spacer which would most likely interfere with the pipe I have.
 
The mailman brought me an OBR power stack and a DT1 filter today. That made a huge difference! This thing screams now.
I’m still waiting for OBR to get the intake spacers back in stock.
 
I recently noticed the truck had a small binding in the drivetrain every now and then. I tore apart all my diffs and found dirt in the front and rear diff cases. It wasn’t enough to cause any damage but it was causing some sticky gears.
I cleaned the cases and rebuilt the diffs using what diff oil I had. I went with 80K center, 40k front, and 20 in the rear. The stuff I poured out was very thin.
This truck is a blast to drive and a formidable opponent vs you’re neighbors vinyl fence.
 
I don’t know how the losi diff cases are sealed if they are at all, but I just used some grease in the groove where the 2 halves of the case meet. One side has a groove, the other has a flange or something that I can’t really think of the name of right now. It’s like a male to female connection. I can definitely see the detrimental effects that fine dirt and dust have on a vehicle like this.
 
I mounted some mad max street sweepers on my stock beadlock wheels and ran it up and down the street for about 30 minutes. The tires are nice, I could tell they had a short break in period as the rear end began to slide a little more and more. No traction roll or flips either. I’m using some DDM shock springs. They are stiffer than stock, which probably helps.
This truck is pretty fast, and I’m honing in on a really good tune. The spark plug wasn’t fouled this time.
 
Back
Top