Laser 200 in line twin - retro fit

[Nigel Dell]

1 hour ago, Jon - Laser Engines said:

DH Comet with twin inlines....drool. But, if you go that route you will need another reverse rotation job so thats 3 engines i can chalk you up for as you need a matched pair for that, plus a 360 inline should i ever get it done....plus, a pair of 160v's for the whirlwind. Sounds very lucrative but the patio scenario could be a problem. 

 

That said, they would all look the same. Just make sure they are not all visible at the same time!

Are you sure she hasn’t employed you as a hitman or at least a setup man?🤔🤭😂

 

I had better check the life insurance 😂

 

I did the same with the moulded gliders, they were all yellow with red undersides, alright one was blue underneath, but my down fall was the all yellow Lunak, it might have been the 4m span and enormous fuselage and chord that gave it away, I barely got away with that, then when we were moving she was helping me carry them and it dawned on her there was far more than one yellow model! And that is when the first injury came🤣

[Nigel Dell]

A little advice required if I may please chaps.

 

On my twins in the past I have generally used two tanks because I had the room, this time I have room for one large tank 16-20oz but the two 8oz tanks would just go in but with no room at all for any isolation materials at all, also meant taking out some structural parts that is too complicated to overcome.

I had intended to just use two pick ups one for each cylinder making it simple and just add a vent to the top of the tank which I do have plenty of room for, I then thought one pick up and a T piece in the feed for each cylinder so bought one of these in the picture, it seems too small and restrictive to me more like a piece for air retracts systems, what is the general consensus of the way forward and what do you use please? Also has anyone sourced more suitable T pieces?

 

Cheers

 

Nige.

 

 

[Jon H]

Our V twin's will not tolerate a fuel T but the flat and inline engines do not seem to care. I suspect this is due to the way the induction pulses overlap eachother. In any event i do not think you will suffer any restriction as the needle is the limiting factor here. I see people going on about big bore tubing to deliver more fuel to the engine and i just laugh as they clearly have no idea what they are talking about. 

[Nigel Dell]

Thanks Jon, they seem a lot smaller in outside diameter ( I know the the work is done on the inside) is a lot smaller than the carb but I have not checked it with the fuel tube yet so I maybe surprised, I take your point as to the needles, obvious I guess but this is sold as a fuel part so I should give it a go, although it is tempting just to use the two pick ups as I originally thought especially if I am correct and this is a source of leaks as I envisage, I will do a more serious check shortly.

[Ron Gray]

I’m using a similar T piece in the fuel line for my 200 FT and it has performed perfectly. Although my existing 160 and 200 in lines currently have twin clunks my new 200 in line will be installed with a T piece.

[Nigel Dell]

I did try out the t piece for fit, obviously looks were deceptive!🙄 the bore is identical to the carbs the fit into to fuel tube I have is fine but I think a clip or binding will be done as a belt and braces to avoid leaks as it is just not confidence building but I will open a new reel of fuel tube to double check the fit, I think my doubts have been because I never use filters or the like inline and was always of the thought the more you put into the line the more there is to cause a problem, I have filters in the fuel bottle and the feed from the pump, never on the model, but thanks Ron I am just going to use the Tee as is I feel confident it will be fine just ensure the fit is secure.

[Ron Gray]

When I first used a Tee on my 20OFT I didn’t wire or tie the connections which resulted in air getting into the line resulting in some nice backfiring. Having zip tied them all the problem has now gone away.

[Nigel Dell]

16 hours ago, Ron Gray said:

When I first used a Tee on my 20OFT I didn’t wire or tie the connections which resulted in air getting into the line resulting in some nice backfiring. Having zip tied them all the problem has now gone away.

Thanks Ron, I was beginning to feel I was over thinking this, I have a habit of taking the longer and harder way round things 😂 I will just use it and tie the connections, it will be accessible to change if needs be but I don’t imagine it would come to that.

[Nigel R]

On 30/07/2022 at 10:53, Jon - Laser Engines said:

I suspect this is due to the way the induction pulses overlap eachother.

 

Pressure pulse moves from one carb to the other?

 

I guess with twin clunks that would have the entire volume of the tank to buffer it?

 

Suppose you could fix it with some kind of float chamber but why bother if the simple answer is twin clunks.

[Ron Gray]

32 minutes ago, Nigel R said:

if the simple answer is twin clunks

Even easier if you also use a fill valve as the three line tank setup can be used.

[Jon H]

22 minutes ago, Ron Gray said:

Even easier if you also use a fill valve as the three line tank setup can be used.

 

As least until the valve leaks air 😉 

 

But yes the general issue is that the V's carbs seem to steal fuel from eachother causing problems but the ft and i do not

[Nigel Dell]

Well thanks to Bernie Jones at Jeti-Fiala UK these arrived today so getting closer to running, nice quality props.

 

 

[Frank Skilbeck]

On 01/08/2022 at 15:34, Jon - Laser Engines said:

 

 

 

But yes the general issue is that the V's carbs seem to steal fuel from eachother causing problems but the ft and i do not

 

Possibly due to the uneven firing and intake valve opening, whereas the inline twins have even spacing.

[Ted Khinsoe]

On 22/07/2022 at 15:42, Jon - Laser Engines said:

 

At the moment i am not sending the inline's out of the UK as its just too complicated if there is problem. I already sent one out against my better judgement and it turned into a nightmare for all involved. Until the testing is finished and it is a standard stock item they are uk only im afraid. 

 

 

ahhhh Jon shes purring like a kitten.  You were up front with your reservations and I'm a happy customer.

[Jon H]

42 minutes ago, Ted Khinsoe said:

ahhhh Jon shes purring like a kitten.  You were up front with your reservations and I'm a happy customer.

 

Yea but it was still a headache for everyone 😞 At least its working now. Has the model flown much?

[Ted Khinsoe]

Sadly the weather has been pretty bad for the best part of the last couple of months so not flown for a while... but then Ive not flown anything!

After its refurb it hasn't missed a beat.  We're coming into the prime conditions for flying so it will get a lot more airtime.

[Steve Dunne]

Hi All, looking for some good advice on my Laser 200 inline twin.

It has flown very well for the past couple of years in an Acrowot XL modified as a test bed, now some 160 flights under its belt.

More recently, it has become much noisier on 18x8 and 20x8 props, with a clicking or knocking sound developing. It is now too noisy for club field flying!

General local opinion is that the front bearing is worn and needs replacing. I have to admit there is a very slight play from the crankshaft in the fron bearing, but my usual port of call for rescue and advice is, as we all know, now sadly unavailable.

I have changed bearings before in more mundane engines, but never in a Laser. Nevertheless, I removed the prop, driver etc., and cleared the front housing, removed the very long bolts, and am now stumped. The front part of the engine appears to be very flush to the crankcase, with some form of sealant/adhesive, and I can see no way of removing it other than blind, brute force??

Suggestions on how to remove the front housing without too much damage(!) very welcome...

 

Steve

 

 

 

[John Rickett 102]

On any other Laser, (and this is just 2 x 100s) the sealant is silicone so won't offer much in the way of an adhesive. The housing should just pull away, they are only a push fit.

[Ron Gray]

A noisy 200 in-line is indicative of the 'design' fault that one of mine has suffered from. The replacement parts have, according to Geoff (AGC), now been returned from heat treatment and will be shipped out to the various in-line customers. Your front bearing looks like it has suffered from rust!

[Steve Dunne]

John, thanks for your reply, but the housing will not move with just a hand grip, and so far I dare'nt use anything else. There is nothing to get a grip on to my sadly ignorant eye...

 

Ron, I did wonder about that. I agree with the show of rust around the bearing, not sure where from. The model is kept warm indoors, and uses low oil fuel.

What is the replacement part? (if it can be revealed online!)

 

Steve.

 

 

[David Ovenden]

How about a pair of large bent-nose circlip pliers. Insert the tips in two front housing bolt holes (but not too deeply so as to engage in the crankcase holes) and rotate the front housing. That should break the seal so you can pull the housing off. Just an idea. I've not got a laser 200 in-line so I've not tried it!

Edited May 13 by David Ovenden
punctuation

[RottenRow]

Bear in mind that the inline must have a different crankshaft design to the single cylinder engines.

 

On the singles, the front housing comes off complete with the crankshaft, leaving the connecting rod big end free to accept the crank pin when the housing is refitted. If it’s tight, fitting a prop. and pulling that gets it off easily.

 

This may be different on the inlines. Perhaps wait and hope for a definitive reply before using any force.

 

Brian.

[Ron Gray]

@Steve Dunne I had exactly the same and don’t know why. I go through the same procedures at the end of a flying day with all of my Laser engines yet the 200 in-line is the only one that had the rust problem! Regarding the replacement part, I’m afraid I don’t know what it is or what work is required to fit it!

[Jon H]

ill add my 2p in this instance to save a guessing game. 

 

Steve, the clattering sound is likely the issue that requires the upgrade part. The engine is also pretty rusty by the look of it and i have seen 3 inline's now that have rusted heavily. I do not know why this should be as i deliberately tested this. To do so i left one of my test engines in a damp shed for about 18 months and while the outside had rusted/corroded heavily, it was immaculate inside. My only thought is my tuning being more accurate, and customer engines are running rich, but this dosent quite add up to me as an explanation and i can offer no other ideas as the one flown in my ugly mustang also seems fine despite a winter in a different damp shed. My suggestion is to contact Geoff and return the engine. Once the new bits arrive i am sure i will receive a summons to sort it out. 

 

I would not recommend further running until its been looked at. 

 

As for the idea of sending the parts out and doing the work yourself...sure, i guess so. But only if i can work out a procedure to do it without completely dismantling the engine and loosing the cam timing for the front cylinder as i dont fancy trying to explain how to fix that mess when they all fall out on the floor. I will have to check my cad drawing notes to remember how to do it myself at this point. 

[Ron Gray]

6 minutes ago, Jon H said:

As for the idea of sending the parts out and doing the work yourself...sure, i guess so.

Sorry Jon, I put that in the post because that is what Geoff said to me last week along with the fact that the parts had been received back from heat treatment the week before last!