Running a Jabiru engine on Mogas?

Finnaly got the answer

200lt drum over $480

thanks for the replies

in Darwin

Hi Rob,

Call Jabiru and get the good oil on the matter.

I know that all the Jab 2200 operating in the Philippines run on mogas but always hi- octane, not less than 95 and the mo-gas there is better than Oz's whilst the diesel is lousy.

Jabiru advise with the motors exported to the Philippines on the minimum reqirements of the mogas to be used.

There is a jab 2200 around my patch that has been running on mogas for years without a problem but I understand that the mtor may have been tweaked in some way.

Regards,

Rick-p

My Jabiru flys in the future. About 3 months worth. In other words todays Avgas price is what you can expect to pay for Mogas in the next 3 months. :ah_oh:

My head hurts.....:big_grin::big_grin::big_grin:

regards

I don't understand the attraction of MoGas in the present RAA flying scene.

Sure it may cost a wee bit less, but all the blokes and blokettes that run it are usually cadging a lift into town, then lugging jerry cans and spilling fuel on their aircraft etc, etc and etc.

And what do those MoGas runners do when calling into a strange airport for fuel while on a trip. It must take them hours to juice up each time.

In my view, the above disadvantages, the mostly good access to AvGas at airports, the stability/quality control of AvGas, and the fact that J engines like it more, more than offset the cost difference.

Or am I missing something?

Regards Geoff

Captain, from my experience most of the 2-strokes run hotter on AvGas (eg 503 and 582) and with them being finniky? at the best of times, the last thing you want is higher temps. Atleast that's what I have grown up to believe when flying 2 strokes.

With running mogas after 80 litre fill up i save enough for a carton of beer price saving over filling with Avgas. easy decision

I don't understand the attraction of MoGas in the present RAA flying scene.

 

 

 

 

Sure it may cost a wee bit less, but all the blokes and blokettes that run it are usually cadging a lift into town, then lugging jerry cans and spilling fuel on their aircraft etc, etc and etc.

 

 

 

 

And what do those MoGas runners do when calling into a strange airport for fuel while on a trip. It must take them hours to juice up each time.

 

 

 

 

In my view, the above disadvantages, the mostly good access to AvGas at airports, the stability/quality control of AvGas, and the fact that J engines like it more, more than offset the cost difference.

 

 

 

 

Or am I missing something?

 

 

 

 

Regards Geoff

You sure are.

I fly behind a Rotax 912 (but I am fairly sure my comments apply to all aircraft engines approved for PULP)

PULP is usually way cheaper than AvGas

PULP is available all over Au, not so AvGas (most petrol powered ground vehicles/equipment run on PULP not AvGas)

In engines approved for PULP, Avgas had no obvious performance benefits blow 10,000 ft.

PULP burns cleaner so no build up of lead sludge in engine/gearbox. Plugs,lube galleries & valve stems, etc stay cleaner - less maintenance cost

Burn PULP in your Rotax 912/914 and benefit from extended oil change/maintenance intervals, saves $$$$

PULP is less damaging to you & the environment.

PULP is good (no deterioration) for at least 6 months when kept in a sealed container.

Up to 10% Ethanol is not usually a problem to engines designed to run on PULP - it may be a problem to other parts of the fuel system eg composite tanks. Many small aircraft builders (especially European ones) now approve up to 10% Ethanol fuel for their aircraft.

Need to transport fuel from nearest suitable PULP servo ? carry collapsible bladder's (I have two x 20 L) & a 12 v high volume transfer pump - never had a problem. Proper planning & communication usually results in an efficient minimum time refuelling.

Purchase PULP from reputable suppliers, with a high inventory turn over and you are most unlikely to have problems with quality/contamination.

If all else fails - use AvGas

You are replying to a thread 12 years old. The 912 is a recommended "run on Mogas" engine and always was. Some engines now allow use of Pulp. That certainly doesn't mean it's the recommended (preferred) fuel. It means you CAN legally use it. Avgas in a Rotax can cause compression loss due to uneven valve seat lead build up as the motor doesn't get hot enough to utilise the lead seat sealing and lubricating properties .Lead does not lubricate valve stems . That's a common misconception. Nev

Well there you go - cant keep a good debate down.

This is my local experience in The Netherlands. I ran my previous Jabiru 3300 exclusively on Mogas (Euro-95) without ill effects. My current CAMit 3300 has 150 hours on it with Mogas as well. Last year after local authorities upped the Euro-95 ethanol content to 10% I started to notice rough running in some situations. I moved to Euro-98 BP Ultrium. This is labelled E5 which means up to 5% ethanol, but we have written confirmation that BP Ultrium for now has zero ethanol in it. Mogas keeps the engine relatively clean.

I could never understand the bogey-man hysteria about running engines on reg gas? Plenty of Lyc/Conty's are running on bogey-man gas??

VW motor's were designed for Pulp.

If I put 95 oc in the HB, it gets higher than normal temps plus sometimes keeps running with mags turned OFF. (summer heat )

Avgas runs the lowest temps, 98 oc works OK when out off Avgas.

spacesailor

Very interesting discussion, but one aspect not covered: 

Will switching to MoGas clean up a Jab combustion chamber after it has run for years on AvGas?

If so, how many hours till it starts to clean up?

 " Will switching to MoGas clean up a Jab combustion chamber after it has run for years on AvGas? "

Try a can of decoke that Subaru use to clean inside their heads. 

OR 

Convert to LPG, That's known to run very clean, even on dirty diesels, even makes them go super economy ( 14 lph down to 10 lph.

spacesailor

A fair% of the build up is dust . There are additives in 100LL to scour lead deposits.(or there used to be) They caused the distinctive whitish hue in the exhaust  pipes. Water alcohol (injected) will remove carbon and boost take off performance and keep temps down. Nev

17 hours ago, spacesailor said:

 " Will switching to MoGas clean up a Jab combustion chamber after it has run for years on AvGas? "

Try a can of decoke that Subaru use to clean inside their heads. 

Thanks Spacey, have already done that once, have a spare can for a repeat dose if needed. 

17 hours ago, spacesailor said:

Convert to LPG, That's known to run very clean, even on dirty diesels, even makes them go super economy.

Excellent suggestion Spacey. I’ll just install the 100kg steel LPG cylinder behind the seat and extend the engine mounts by 150mm to maintain CoG.

I think the only way you'll find out is after a period of time running mogas & having a look. I've run my 3300A on mogas since new & only use avgas when I can't get mogas which is not very often. The pistons/head/valves look clean & the plug ceramic insulation stays white. The electrode is usually black but there is no buildup. The exhaust pipe is also black. That's pretty much the same as my car.

Thanks for the reply, Kevin.

I’m still a bit wary of totally converting to ULP, so plan to have AvGas in the right tank and 98 ULP in the left.

Then I can use the certified fuel for critical phases (TO, climb and landing) and switch to ULP for cruise.

I hope that reduces the amount of lead buildup in the combustion chamber.

The diesels only have a very small amount of LPG Ontop of the diesel.

If the diesel runs out, it Can blow the motor, So a 100klgm tank is not needed, even when running for 400 klms at a time.

spacesailor

As I embark on finally getting to fly my Jab 230, I have been advised by a LAME familiar with Jabiru engines, to try and stick to BP 98 mogas. As its not available where I live (Caltex 98 is), can anyone shed anymore light on why BP may be the best?

Some years ago there was a debate regarding the best brand of Mogas to use. The consensus then was BP 95 due I think to the quality processes and guarantee of no ethanol. Since then many BP service stations no longer stock 95 and have gone to an ethanol blend which is 94 RON. 98 does not have ethanol in it so most have converted to 98. I use Shell 98 as that is what the Liberty servo stocks around the corner from the aerodrome &  they are on a busy road so the fuel is always fresh. Each brand has its own blend of aromatics to attain the octane rating & provide clean burning. There is virtually no difference between major  brands IMO. Ask the lame what his reasons are. You may well find it is that is what was said some time ago and no-one has challenged it.

After having to use some avgas intermittently, I'm running BP 98 and Decalin.

Normally I use caltex 95 and have had no probs with it but 98 is relatively cheap at the moment and the added additives may help the cleaning.

After 20 hrs, the plugs looked cleaner.....I've changed them now.

I'll probably just keep adding the decalin for the hell of it.....

Rotax 912 uls.....

Petrol supplies are "generic". It's mostly refined in Singapore to meet Australian fuel standards and when the oil tankers arrive in port, the refined petrol is pumped into tanks in fuel farms that are often not even owned by the company buying and selling the petrol.

Road tankers from a dozen different brands of retailers draw their fuel from the fuel farm tanks. The only difference between brands is an "additive package" is sometimes added to the road tanker on fill up, for different brands, or "premium" brands, or to upgrade the octane rating. This info comes straight from a fuel terminal manager.

I use Caltex 98 from the same dealer,and he told me it is tested every 2 weeks,i have no idea what tests they do.He also told me it's the same fuel

as the Woolworths BP 98 up the road.

Colin 

Bloke walks into a Caltex station with a BP mower fuel can and says “ Can a BP”. The attendant replies “ I don’t know but fish can fart, I've seen the bubbles”.