Lyndon

Guess really what I'm saying is a mechanical pump any better than an electrical one. I can answer that. No one makes a mechanical pump any more. So two separate circuits two pumps should be fine. Yep no one makes a flat tappet engine either. Unless your Rotax. . They do both because it works. Not great but it works. If they were building car engines they would be broke. I totally understand the litigious society we live in. It's a Shame really.

I may be wrong. But you kill every thing. What I do know is the engine still runs if it gets fuel. The battery still has a full charge. On a complete redundant circuit is another pump. Has to have 30 to 60 mins in it. Pumps don't fail and wiring looms don't burn for no reason. I'm very particular in what I do and I would be very surprised if you needed the second backup. Then the third is to land which is easy in a Savannah. But like I say I'm new to this so I really appreciate your comments. Lyndon

The battery is still alive after a master has been cut

More likely a wing to fall off than two circuits fail at the same time

The master does not turn off the engine. It still fires the plugs. What I'm saying is two separate fuel pumps. Easy to wire on two curcits

Yes I get that. Cut all electrical power and hope it stops burning. All being well the engine keeps running as it produces its own power. But on a redundant loom is your back up pump. It still pumps ???

Update. The main thru bolts are a torque to yield arrangement. Without checking 15 nm plus 180. I'm doing some research but in my industry torque to yield are one off use. I will get back to you. Ps I have to tool to remove the rear the engine if any one needs that. Also I'm about to do the gearbox service and preload. If anyone has thought of saving 600 bucks and doing it themselves. Lyndon

I'm new to this but I have a mechanical background. I understand why we have a back up pump. One electric and and mechanical. The electrical backing up the mechanical. I'm building a Savannah. I'm freshening up a 912 uls with 1740 hrs on it. I have priced a new mechanical pump. Outrageous. Why not fit an electric pump. Separate circuit that runs 100 %. This will easily do 2000 hrs. I have a back up. Chances of both failing are no more than electric and mechanical. Engine looses charge rate I'm guessing after shutting down excess power the battery will run it for at least 30 to 60 mins. Battery dies then as long as the engine is running it has power. I'm guessing the efi engine that Rotax make does not have a mechanical pump ???. Like I say I'm new to this and appreciate any input. Lyndon

Update. I've been waiting for a crankcase Dowell. Anyway pulled the lifters apart and cleaned them. Absolutely perfect at 1740 hrs

Does anyone have a crankcase Dowell. I have lost one Lyndon Wright

I think that is being polite. Why would anyone like Rotax buy an off the shelf oring for a dollar then sell it through their network at twenty dollars. Makes no sense. Just mark it up three hundred percent and sell it for three dollars. Then everyone is happy. The rings were outrageous but I didn't have much choice there.

I priced up genuine orings. Gee it would run at about 700 bucks. For one tenth I bought off the shelf jobbies. Almost 29 plus gst for a rocker cover o ring. Plus over 4 for the center bolt. There are no words to describe it. Lyndon

I could not find any info on splitting the cases. Maybe you all know but case bolts studs etc is 25 nm. This seems to be secret. Cam timing is a breeze. Replace to two orings. Use three bond with a one not a two. Five dowels . Apart from that there is nothing else in the cases. Easiest thing you will ever do. Nitraded cam and hardened lifters. I don't think that works but I'm no expert. It was worn at 1740 hrs. So I'm guessing at 1000 hrs it would have been comprised. If Rotax got rid of the 1920s flat tappet cam I would not not have to do this. Lyndon

That's it correct

Ivan Teigh cams in Brisbane. I've spelt it wrong but Google will grab it. Speak to Dean.

Update. I have split the cases and had the cam and lifters reground. I wasn't happy with new lifters on an old cam. The cam is nitraded. So hard as cats head for probably 2 thou then it's cheese which would explain some failures and why they go suddenly.they did give me the numbers but it's good now and should do another 1740 hrs with a better oil in it. Heads passed the softness test with flying colors.

Yes I'm replacing my rings. My motor has 1740 hrs on it. The heads are like new. I lapped my valves but ever so light. Seats and valves have ton left on them. If you blued them and had a good seat with a good valve I can't see why it would be leaking. Maybe pull that head and get it looked at. I don't know your level of expertise but if you take it somewhere be careful. Everyone is an expert. You can cut the Seats but not the valves. Are you in SA . Lyndon

For interest I had my heads tested today for hardness. 1740 hrs of use. They are above 100. Apparently 130 140 when new and 60 you really have to give it some thought. So pretty good really. I'm thinking the heads would be good for another 1740 hrs. Lyndon

These are not the drain holes for vents are they. I need to drill them Lyndon

Thanks for pics. Looks very nice. Opinions on matting for the tanks. Book recommended top and bottom. I have got some rubber. I guess enough just to stop rubbing. When I washed the tanks out I just could not believe how heavy two tanks in each wing will be. Thanks Lyndon

Breathers of the four tanks. Manual says I holes top and bottom skins. I can see the top but the bottom hole is a drain ??? Inner rear location. Correct. So the existing hole in the top is redundant with the auxiliary tanks. Any tips ??? Or just drill a hole in the top and bottom to suit. Any pics would great. Lyndon

I have just done all four tank outlets. Was very much not impressed with the set up. But I removed two outlets after 24hrs to inspect the sealing. They look perfect and I'm now confident they will be fine. An overnight leak test on all outlets before fitting.

Yes I could imagine that buzzer would not be a nice thing

All very interesting. Would I be correct that only air lock issues would arise if you were to run a tank low ???

It's interesting about the header tank. I can see that as it fills initially the air has to go somewhere. I'm guessing as no tanks get low there would never be problem