Unknown Petrol Engine & its Hall Sensor

[Rich Griff]

I stand corrected, bmr6f is a tapered seat type plug, so no washer.

 

You live and learn...

[Andy J]

More pictures of the Walbro carb I need to identify.

[john stones 1 - Moderator]

4 hours ago, Andy Joyce said:

From a quick search looks like the NGK type to replace the Jenn Feng type is a BMR6F.

 

Carb pump tube does indeed look naff so will replace before running the engine for the first time.

 

Engine Doctor.... do you know the Walbro type used on the Thor 45 as a search on ebay threw up quite a lot of carb kit variants.

 

Should be numbers on your carb to identify parts.

[Andy J]

Could not see any ID marks John but will look again.

[john stones 1 - Moderator]

3 minutes ago, Andy Joyce said:

Could not see any ID marks John but will look again.

 

 Might need to take covers off, they are stamped in various places on assorted carbs Andy.

[Engine Doctor]

Buy a walbro carb service kit that includes the WT variant. That will have a diaphragm to suit the carb.  Mine didn't have any name on it as its a Chinese copy of a walbro but works OK. I believe the CRRC and the Thor were the same engines just branded for different ddistributors. Seeing the extra pics it looks to be the same just dresse up in different colours. Other things to watch out for is cylinder base screw can strip out easily but is a simple repair with helicoil or a longer bolt with a locknut. Excessive end float or rock developing on the crankshaft. This fault on mine needed shim making up. Also the bearing were loose in the case so needed a application of " locktite bearing fit " 

That was some years ago . Mine still runs well and is a powerful old lump and is fitted in a Eurobat 80 inch model. 

With the introduction of E10 petrol I will be making a batch of fuel with the ethanol removed. This should prevent damage to engine internals and carb diaphragms . 

[Andy J]

Just looked again over the carb and found the ID as a WT 138 664A.

[john stones 1 - Moderator]

That should get you sorted Andy, bit of google and bobs yer auntie.

[Andy J]

Is it just likely that the pump diaphragm that will need replacing? As I say the engine has never been run so unsure if the carb will have suffered internal damage over possibly many years in storage.

[john stones 1 - Moderator]

You'll see when you strip it Andy.

 

[Andy J]

What type of damage do you look for John?  I assume perforated or brittle gaskets.  Little reluctant to strip the item till after I give the engine a run just to see if it runs at all.

[john stones 1 - Moderator]

I change it all Andy, carbs in bits, seem the thing to do, some seals split anyway, I use carb cleaner on it and airbrush to blow jets out.

 

Ah, didn't realise you hadn't run it yet Andy, give it a go first then.

[Andy J]

Will do John, Chinese kit on order just as a back-up anyway.

[Mike T]

I 'made-over' a carb last week and used this carb kit.  It came with diaphragms and reeds that are (supposedly) E10 compatible.  I swapped out everything I could and it started first pop.

[Andy J]

Good to know Mike. Have never stripped down a petrol engine carb but assume it cant be that difficult.

 

Placed an order today for a new BMR6F plug as well as some screws to mount the exhaust which from crude measurements are M5x20 with a square nut.

[cymaz]

This video might be of use. Don’t fret about the special tools they use, you

l get the general idea. I’ ve never had the courage to remove and replace the welch plugs ( if that’s what they’re called)

 

 

[Andy J]

Thanks Cymaz will look at this video again once I get my carb kit.

[john stones 1 - Moderator]

Carb kits normally come with bits you won't need, some bits are common to carbs other than yours, so don't sit scratching your head or thinking they've sent the wrong one Andy.

[Andy J]

Well M5x20 are a tadge too short for the exhaust so will need to order a pair of M5x22 and M5x25 just to be safe.

 

Given how I hate how the exhaust sticks out of the cowl have also ordered a Pitts style muffler which was originally made for a Zenoah 45, so fingers crossed that it fits. Certainly the manifold fixings are at the right dimensions of 42mm but unknown if the main barrel of the silencer is stood far enough off from the Thor cylinder head. Time well tell but no great loss if not as the exhaust was under $30 including delivery from China.

 

 

[Mike T]

On 03/10/2021 at 06:22, cymaz said:

 I’ ve never had the courage to remove and replace the welch plugs ( if that’s what they’re called)

I did the bigger Welch plug!  ?

The vids make it look easy.  You think they are going to be fairly soft and that you can easily push a pointy tool in.  Mine was horribly hard and I had to force the issue with a small hammer.  It's as well they're not re-usable 'cos when the blighter came out it pinged across the workshop....

Edited February 16, 2022 by Martin Harris - Moderator
Try to use a bit more thought than simply changing a single letter of a word contravening the CoC!

[Andy J]

Did try fitting the Pitts Silencer but even more of the engine protruded from the cowl so have now acquired a DLE35RA which allows for an in cowl installation in the Sparrowhawk.  So if anyone is looking for a cheap 45cc petrol engine with zero hours then please feel free to send me a PM. 

[cymaz]

i think you find the dle will more than meet your requirements....a club member is delighted with his