Dear All,

I would need some help,today Ive flown my .46la & later after it went dead stick,Landed it.I let it cool down & then tried to re -start but there was very little compression,therefore pack up & went home,At home again tried but no result,after dis-mounting the engine,checked for leakage-back plate,glow plug,carb all ok,filled fuel & pumped in air but no leak,Before all this I had slightly opened the carb 1/2 turn to run engine cooler & tried starting engine,again i returned the carb needle to it original place but still compression.

What could have gone wrong?
Engine is almost 2 year.

Peter,

It sounds like you have a leaking head. If not then you have a peeled liner.

Put some oil in the engine, hold it with the head down and see if oil comes out around the head gasket area?

Pull the head off and look at the cylinder walls with the piston down out of the way and see if the nickle has peeled away from the brass liner in places?

Good luck,

Jim

If you're really lucky you might have only blown the seal on the glow plug. Dribble a bit of fuel over the plug then check for bubbles when you turn the engine over.

Dear ALL,

yesterday again I sat with my engine,checked for the oil leak after filling but no leak,Remove the head all ok & again tried fliping the prop ,no result,later when I had a close look at the carb,seen a very small crack in the carb beside the AIR BLEED SCREW.Could this be the problem??????????????.Today will remove the carb & try to bold the hole with finger to see the compression remain same.

friend of mine adv to use a nulon sealent which give a coating on the valves which can crreat a good compression & this is used in two stroke engine-mobikes.Is the idea goods.

I agree that there is a leak some where?Can I submerse the engine in water or oil & when check of air bubles after putting a big tubing to muffler exhuast/nipple. or is there any method to check leakage.

The carburetor has absolutely nothing to do with the engine's compression. The engine backplate has absolutely nothing to do with compression. Compression is created exclusively in the cylinder.

You must have a leak around the glow plug, a leak around the cylinder head, or a leak around the piston. There is no other reason for reduced compression.

There are some subtle hints in your original post that lead me to believe you've probably ruined your engine by running it too lean:

1. It went dead stick.
2. You had to let it cool down.

You can easily ruin an engine by running it too lean, just once.

The LA series has a very thin sleeve and the appear to be very unforgiving of a lean run.

One other thing to check is that the head is a porus casting and may have pitted through. We've seen this a few times. Clean the head well and see if there is any pitting on the head, chances are that its gone through.

Dear mkirsch,

You r very right yesterday I opened the head & removed the sleeve & noticed that the inner o the sleeve had tuned golden & worn off,can see some very fine line which I think is caused due to engine heating.

NOW the big question come,any other solution before I get a lot of suggestion to change the sleeve.

In india,to get the sleeve from tower hobby would takje at least 1 month & secondly I will again have to pay a duty on that sleeve & they will ask million Q.

ANY OTHER SOLUTION ?

It's not cost effective to repair that engine even in the States. Set it up on the shelf to show your friends.

Buy a new ball bearing engine that's some other brand or model.

Jim

probably ran it too lean....

petergnomes: If your chrome is not peeling , put the sleeve back in , making sure you get it in the same position. Put the head back on & tighten the screws evenly. Take some regular drug store Castor oil & with the piston 1/2 way up put 6 drops of oil in plug hole, replace plug & with carb wide open flip the prop & see how compression is now. If it feels better add 8 oz of Castor oil to your fuel. De gummed if you can get it (maybe motorcycle shop) . When I was a kid my buddies & I used to do that with our old Fox engines & were still able to hand flip them. You could also remove the head gasket & lapp the head to the sleeve top with fine valve grinding compound or rubbing compound. Worth a try to keep you in the air!>>>>>>>>big max 1935>>>>>>>>>>>>

Dear ALL,

I ve cleant the entire engine with kersone soaked for 2 days 7 cleant it with methonol & re assembled it & added a little oil,still the compression is less,my friend has asked me to send the LA to his place as he has one LA ENGINE With a broken con rod,he would spare me the sleeve & piston & also would check both.hope I'm lucky & may the engine revive.

SECOND thought to my mind is that Im going to buy a new MVVS engine may be a .45 abc or a .49.Just need to know whether MVVS is better or enya as I understand that OS is presently not good enough compared to these engine as they are built in mass production & quality differs,pls adv.

ANY COMPARISION SHEET is availble onthe net.

Hello!
The .40 .45 and .49 MVVS engines with the new standard carb (No 3216, 7mm intake and No 3219, 8mm intake) are very good ,as good as OS or any other manufacturers carb.
These engines combined with the ultra muffled silencer (No 3245A)(not the tuned minipipe) are going to please you very much if you try them out.

Regards!
Jan Karlsson

Dear Jaka,

Received a confirmed mail from my dealer as he is selling me as per below


Price- for .45- $113 including sales tax & courier

WARRANTY FOR 6 MONTH ON MANUFACTURING DEFECTS.

carb no :3216
silencer :3245- STANDARD.
SIL- 3248 -$25(want to see a photo of this silencer) & good effects.

Glow plug -ROSSI COST- Rs.200/-

.49 -$126.00

PLS SUGGEST WHICH ONE IS BETTER,IS THE .45 OK???
Reason being that Ive only 10x6 prop & I would be using these prop only.

thanks for your suggestion.

DEAR all,

IM STILL AWATING FOR YOUR ADVICE IN BELOW MAIL.

PLS

i have a .40 and a .45 . these engines run great but they take more time to break in and need more attention/tuning as compared to OS and TT.

as far as props are concerned...i run these with at least 11 inch props for the 10inch gives too much rpm. they love APC and wooden props.

what are Thunder tiger prices like ?? if they are cheaper then I guess you can put them as another choice.