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Bench break in

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dubdeuce

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I just received my 367 hot mod and I wanted to break it in on the bench. DO you feel you must have a load on the motor to break it in. I plan to run 5 tanks at wot on the bench and then two tanks in the car. I dont have a onroad exhaust system so I cannot put a prop on the mil thanks
 
Not wise.
Airplane engines can be broken in this way since the prop not only puts a load on it but also keeps it cool.
Any reason you can't install it and break it in with the normal break in recommended by the manufacturer?
If you want to break it in on the bench, use the heat cycle method, but do NOT use WOT for it.
 
Rolex said:
Not wise.
Airplane engines can be broken in this way since the prop not only puts a load on it but also keeps it cool.
Any reason you can't install it and break it in with the normal break in recommended by the manufacturer?
If you want to break it in on the bench, use the heat cycle method, but do NOT use WOT for it.
Click to expand...

That is true if they are not richening it fully

I used the heatcycle method for and OS21 RG . In fact, XRC did a great article on it recently. Adam Drake did the break in.

Going WOT during the heat cycle method is fine so long as you are richening it up AND keeping a certain temp. You can actually do this in the rig or on a break in stand . I did mine on the rig itself since I am broke. LOL.

Anyways, doing break in tanks in idle is not all that great IMO. The way it was done in XRC is very similar to how I have done it. They keep a lower operating temp of 170 ish to 190 I believe but I try to stay at a temp of 200 F.



How do you plan to do yours?
 
I just got a ceo power modds nova 21 plus,ceo hand laps the engine for you as part of the break in,it was the best and most easy engine i have ever put in a buggy and fired up,they say race ready out of the box,I have ran five tanks and it took a good tune...in the future look this guy up or amain sells his mills well worth the money!!!!!!!!!!!!!!!!!I also have the nova 367 and just keep in mind that mill will be a complete dog till 1-2 gallons than it will come alive,my buddy found this to be true also took well over a gallon befor the motor got good..and man what a bitch to break in!!!!!!!!!!!!!hope ya have a heat gun...super tight pinch..again take your time and get some fuel through it it realy takes along time for this mill to wake up...
 
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I made a break in bench for airplane and car engines. Since I had a large variety of props laying around I made a belt drive system that would put a good load on the engine. It worked for winter months with a pipe running out of the garage but in the vehicle is much better. I like the heat cycle method much better and the WOT I just don't think is a great idea. Sure Drake can do it because his engines are all free. So what if they only last 3 gallons he has a couple dozen "spares". I like mine to last awhile because I can't always drop $200 for the fun of it.....lol. I would stick to the more traditional methods if I was you. Just IMO.
 
i have read the Rb forum and this is how they do it at the factory.
2 tanks wot temp 80 C
2 tanks wot temp 90 C
1 tank wot temp 100 C

then they run it in the car for 2 tanks to get the proper tune.
 
I am currently on 2.5 gallons on the OS that was done the way Drake did. I don't see how anyone can say it will last for 3 gallons only. When I get to 3 gallons I will let you know what happens and if there is any decline in performance. Mine is just really showing power.
 
jon2 said:
I am currently on 2.5 gallons on the OS that was done the way Drake did. I don't see how anyone can say it will last for 3 gallons only. When I get to 3 gallons I will let you know what happens and if there is any decline in performance. Mine is just really showing power.
Click to expand...

I got 12'ish through my 21RG before I had it pinched. I used the typical heat cycle method for about 8 tanks, then tuned lightly to 12 tanks for performance. Around gallon 14, the rear bearing got loose and I replaced them both. It's in my aftershock for the winter now. It sat in a baggy for about a good year. Started on the 2nd pull! They may not be the most powerful engine, but dependable as all get out... except when a con-rod, bearing ball or crankshaft snaps in half... But that usually happened before gallon 2...

It would be interesting to see the difference. Please keep us posted!
 
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I two have the os 21s and they are great engines,i broke it in the old school heat cycle way and after break in put a new rod and bearings,this thing is on like gallon five and it killer!!!!!!!!!!!!!!!!!os engines are great if you change out the crappy bearings...
 
wow Pretty pricey to replace the conrod and bearings after break in. Why not just keep them till they get sloppy
 
jon2 said:
wow Pretty pricey to replace the conrod and bearings after break in. Why not just keep them till they get sloppy
Click to expand...

The bearings are a known problem on the os mills and well I had the conrod from another mill i just sold and never rebuilt..but i have to tell ya after a break in the rod bushing takes alot of stress and was loose changing it was cheap insurance i think....
 
i have an ofna force 21 engine and just replaced both bearings, AU$60, about US$55-ish. is it normal for the rear bearing to be somewhat loose, as in about 0.5mm play? i replaced it anyway and this new bearing is smooth and nice, though i can't really test it, the engines still playing up, but thats for another thread.

BTW, is it cheaper to buy bearings from the LHS or a bearing shop, i bought mine from a bearing shop?
 
hvymetalalchmst said:
i have an ofna force 21 engine and just replaced both bearings, AU$60, about US$55-ish. is it normal for the rear bearing to be somewhat loose, as in about 0.5mm play? i replaced it anyway and this new bearing is smooth and nice, though i can't really test it, the engines still playing up, but thats for another thread.

BTW, is it cheaper to buy bearings from the LHS or a bearing shop, i bought mine from a bearing shop?
Click to expand...

I have no clue what is cheaper,i whent with the tko stuff,I bet fast edyy on here could hook it up the best!!!!!!!!!!shoot him a pm great guy and fast shipping!!!!
 
hvymetalalchmst said:
i have an ofna force 21 engine and just replaced both bearings, AU$60, about US$55-ish. is it normal for the rear bearing to be somewhat loose, as in about 0.5mm play? i replaced it anyway and this new bearing is smooth and nice, though i can't really test it, the engines still playing up, but thats for another thread.

BTW, is it cheaper to buy bearings from the LHS or a bearing shop, i bought mine from a bearing shop?
Click to expand...

Find out what type of bearing from the manufacturer used on the engine and see where they are cheapest.
 
I highly recommend bench break in.....YOU NEED THE PROP....the load is essential....not sure what stand you have but do yourself a favor and buy the correct mounting kit with the shield for it......
I do the same breakin as the RB process you mentioned except I stop each cycle every 2 mins and let it come back down to less than 100 deg F.....then run it again...get the temps to 200 on the first tank...and every 2 tanks raise it 5 deg running the same 2 min cycles of letting it cool down and restarting it....the important thing to do is control the expansion and contraction of the piston and sleeve as best you can..you do this by immediately increasing the throttle position to an almost WOT....keep temping the the head and adjust the high end screw until the temps are right where you want it.......the first few tanks will need to be monitored closely as you will need to adjust the screw more frequently.......so one of those venom temp systems is a big help (double check with a good temp gun as well).....also run a long tube connected to your exhaust pipe into a bucket of water...this will make the sound almost bearable.......tie the tube (any type will do as long as you can tie it to a heat resistant exhaust nipple.....I have over 20 GALLONS of fuel on my rossi P5 and it is still tight 3 gallons on my OS RZ-b since I rebuilt it and it's still tight.....I had 3 RGs I broke in this way and are probably still being used by a few members on this site......it is so much more controlled than doing it in the car but it's load and obnoxious for about an hour and a half if you do it straight through.....
 

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