| Author |
Message |
    
nev_b
Member
Username: nev_b
Post Number: 5
Registered: 03-2015
| | Posted on Monday, March 30, 2015 - 01:01 pm: | 
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http://youtu.be/7Z27XQYr29k
Here is a link to my RJ1 running at a small show yesterday, the engine got warmed up nicely and did not smoke, I did have a problem keeping the speed constant, it would speed up or slow down even with the throttle lever locked up, a bit more looking at required I think |
miro
Senior Member
Username: miro
Post Number: 809
Registered: 11-2001
| | Posted on Thursday, April 02, 2015 - 07:06 am: |
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It could be that , with no load and at idle, you are getting some residual fuel building up in the passages and the cylinder, because the engine is not up to good operating temperature. Once that residual fuel is consumed, the engine slows down again.
As a show engine, that's OK, except that over time, you may find excess carbon build up occurring.
The best thing although probably the most challenging thing to do, would be to put some form of load on the engine.
miro |
nev_b
Member
Username: nev_b
Post Number: 6
Registered: 03-2015
| | Posted on Friday, April 03, 2015 - 04:24 pm: |
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That sounds like a good idea, I could perhaps run something form the coupling at the rear a generator maybe ? That would give it something to do, I saw a nice set up last year at a show in Holland, a guy had a 1940s Skoda marine with a propellor in a Perspex box full of water , I,m not sure if that would give it much of a load though ? |
miro
Senior Member
Username: miro
Post Number: 810
Registered: 11-2001
| | Posted on Friday, April 03, 2015 - 09:58 pm: |
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The water box will give enough of a load to help smooth out the engine speed. If you run it for more than 5 - 10 minutes, the water will get warm enough that you will be able to tell the difference.
A generator might be a little more complicated, but at least you wouldn't have to fuss with the water.
You'll likely put some light bulbs as a load on the generator, and for sure you'll see them getting brighter and dimmer as the engine speed varies.
miro |
nev_b
Member
Username: nev_b
Post Number: 7
Registered: 03-2015
| | Posted on Saturday, April 04, 2015 - 10:28 am: |
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I,ve remembered that I have a 12v Dynastart under the bench, if this were fitted along with some bulbs for a load ?? |
ernie
Senior Member
Username: ernie
Post Number: 2044
Registered: 01-2002
| | Posted on Saturday, April 04, 2015 - 06:37 pm: |
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If this is a true diesel (not hot bulb) it should idle smooth with no RPM variation. Unless you have it set below the specified idle speed.
I suspect something isn't quite right with the injection pump and or injector. Maybe even governor springs. It for sure shouldn't need any load to idle smooth/consistant as it is designed to idle in neutral just as well as in either forward or reverse.
Hope this helps
Ernie |
nev_b
Member
Username: nev_b
Post Number: 9
Registered: 03-2015
| | Posted on Monday, April 06, 2015 - 11:58 am: |
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I have not found any sign of a governor on the engine which is strange? I am going to delve a bit deeper into the crankcase, when I work out how post pictures I will do |
ernie
Senior Member
Username: ernie
Post Number: 2048
Registered: 01-2002
| | Posted on Monday, April 06, 2015 - 06:41 pm: |
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My comment was based on diesels in general.
I have no specific knowledge on Thornycroft engines.
What is in the housing under the injection pump besides a cam?
Is the only throttle control the lever that is hooked directly to the pump rack?
If the throttle lever is the only connection to the pump rack I suspect there isn't a governor.
Hope this helps
Ernie |
nev_b
Member
Username: nev_b
Post Number: 10
Registered: 03-2015
| | Posted on Tuesday, April 07, 2015 - 10:19 am: |
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As far as I can see there is just the cam to drive the pump and a lever that goes to a push button on the outside , pushing this operates the pump to prime the fuel line to the cylinder, there is only the throttle lever connected to the rack . |
jimdereynier
Senior Member
Username: jimdereynier
Post Number: 108
Registered: 08-2007
| | Posted on Tuesday, April 07, 2015 - 06:49 pm: |
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Thanks Ernie for the "hot bulb" statement. Fascinating reading on the web. At the next antique tractor show, I will have several questions to ask. |
nev_b
Member
Username: nev_b
Post Number: 11
Registered: 03-2015
| | Posted on Wednesday, April 22, 2015 - 11:49 am: |
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Here is a link to a picture of what is under the housing that the fuel pump sits on ,
http://i234.photobucket.com/albums/ee5/sludgemonkey/IMGP2567_zpsf6nvd6tc.jpg
as you can see there is no governor just a direct drive from the cam . |
