Solex-30FV

The place to discuss all matters relating to David Brown Tractors. You will need to register your user name before you can post. If you have already registered could you please make sure that your location details have been completed. Go to My Account in the Main Menu on the left, and then go into "Edit Your Information" and complete your location details. Give the Country (and State/Province if you wish) if outside the U.K. County if within the U.K. Location details helps other members if you need spares, technical advice, or the nearest practical help.

DISCLAIMER -

David Brown Tractor Club Ltd
Forum/website Disclaimer

1. This [forum/website/chat room] and the advice and opinions expressed herein is not a solution for mechanical, electrical, valuations, other problems, breakdowns or issues experienced in relation to the vehicles referenced.

2. If reliance is thought to be placed on any of the information guidance or input provided such information will be expressly confirmed as appropriate to be relied upon.

3. In the absence of any such confirmation no reliance should be suggested or inferred.

4. Members must not disclose information to 3rd parties in anticipation that reliance will be given by non-members.

5. Non-members must not purport to give advice on behalf of David Brown Tractor Club.

6. If you or someone you know is experiencing difficulties or repeated breakdowns you must seek assistance for an appropriately qualified expert who holds themselves out as such.

7. Any comments are free of charge and made or posted on an ex gratia basis. No member or non-member may advertise their professional services

Any user inactive for more than 3 months will automatically be deactivated, please contact admin@dbtc.co.uk if you would like to be reactivated.

Please be aware that your user name and entered location can be seen by all members. We only store information you have entered which is your email address and username, your IP is also stored, we have no access to private passwords.

If you do not agree with your information being stored, please do not register an account, If you wish to unsubscribe at any time please email admin@dbtc.co.uk giving your username.

Amended 27/10/18

Moderators: Segrie61, admin

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Sun Nov 03, 2019 5:19 am

Hi Geoff,
Sorry I meant to reply to you about the timing light before.
Condensors come in various capacities and in order to buy the right size I need to know it's value. Other value ones will work but can cause the points to pit if it is wrong. I have a spare condensor from a Holden Red engine that will physically fit inside or I can use a film capacitor (21st century version of a condensor).
All the HT leads and coil lead are brand new copper cored with new plug ends fitted and I re-used the tiny brass washer at the cap end again but cleaned them first. Using the multimeter there is 0.00 reading on the meter when set to ohms which is exactly what you strive for.
At the moment I am using a brand new coil and I did hook up the original and it gives the same results as the new one so the coil/s are good. Especially when you see a big fat spark jump over a 3/4" gap and crack like thunder. I will try the spare condensor I have and see what happens tomorrow.
Now to find my timing light might be a challenge as it hasn't been used for a light year, no pun intended. If I can't find it I can use a 12v light in place of the timing light. At least when I did the rebuild all those years back I remembered to clean all the marks on the flywheel and put white paint on them and wipe off the excess to reveal the fine lines you need to see. Again a tomorrow job.
No doubt more info to come soon.

baron_beeza
Posts: 19
Joined: Sat Jun 29, 2019 1:25 pm
Location: NZ

Re: Solex-30FV

Post by baron_beeza » Sun Nov 03, 2019 7:44 am

Following this thread with interest.

I noted the pic of the needle valve and top portion of the carb. it shows the removable tube in the air tract which I guess could be called choke tube, venturi tube or similar.

Has anyone encountered a 30-FV from a Cropmaster that doesn't have that tube fitted ?

I had a carb apart this afternoon and it didn't look like the one we are seeing here.
It had the screw that would normally pin that tube in place but there was no sign of a tube itself. The tractor had been running, and not so bad at that.
Attachments
20191030_140026.jpg
20191030_140026.jpg (90.69 KiB) Viewed 166 times
Last edited by baron_beeza on Sun Nov 03, 2019 10:31 am, edited 1 time in total.

User avatar
GeoffDEAL
Posts: 456
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: Solex-30FV

Post by GeoffDEAL » Sun Nov 03, 2019 9:52 am

Hi baron my old parts books show it in two sizes havnt seen a carb without one yet. cobbadog found the value of all DB condensers in an old thread by db2d should be 1. microfurad --1.uF also one manual lists points at 0.015 maybe better if shaft has some movement, on one of mine you could open and close the points with shaft wear had 2 sets of bushes but wear always came back,shaft was probably worn to much. cheers Geoff

baron_beeza
Posts: 19
Joined: Sat Jun 29, 2019 1:25 pm
Location: NZ

Re: Solex-30FV

Post by baron_beeza » Sun Nov 03, 2019 10:45 am

Thanks Geoff. I have been doing some reading and it definitely does seem like there should be a choke tube fitted.

The tractor obviously runs on the idle and other lower power circuits before the venturi provides the suction to bring the main jet into play.

I bought another Solex carb this afternoon and although it is a side draft 30AHG I was hoping the banjo fitting, float and needle valve could be swapped over. It was only $10 so It will not be the end of the world if nothing is of use. I think they were fitted to Morris vans so there may be a market for it.

That carb won't be here until Wednesday so I may get a chance to revisit this job first. It will be interesting to see how the engine runs if I can find a venturi to fit in.
Attachments
IMG_20191103_165620.jpg
IMG_20191103_165620.jpg (126.34 KiB) Viewed 161 times

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Mon Nov 04, 2019 5:18 am

Thanks yet again Geoff,
1 micro-farad is small capacity wise, most read between 1.8 - 2.2 uF and the condensor in my distributor is not marked on the bottom of it as they would be normally.

Hi baron_beeza, yes the choke tube is there to enhance the venturi effect and the manual shows 2 different size choke tubes for different engines and the other size is smaller so might be for the 25 engine. I can only imagine that it wont run without one but I don't know this for sure. I have the choke tube size written down on my paper work out at the tractor but from memory the size on it is marked 24-30 or visa versa.

Anyway on a lighter and more positive note the engine is now running far better with room for improvement. I fitted up the borrowed carby and started the engine. It was missing on a number of cylinders but had a huge spark at each plug and only 1 1/2 cylinders appeared to be firing. Swapped over the ones not firing well with 3 old plugs and it this improved things but still not happy. dug out the timing light and removed the cover on the bell housing and turned the engine over to approaching TDC and the marks were coming up. The manual says to put the letter "M" in the centre of the hole, I have no pointer on mine, and at this point the points should be just breaking but mine were opened more than 'just'. So using a test lamp I loosened the distributor bracket and rotated the it back so that the light was on and slowly rotated the distributor until the light just went out. At this stage this is where the manual tells you to set it to and should be 7' BTDC. It started up ok but was occasionally back firing through the exhaust so I moved it a little bit and until the engine sounded as smooth as it could be at this stage. I lock it up at this point and went back around to the carby where on full throttle the engine was not too bad but at idle it was not quite so good and I moved the mixture and got it as good as it could be. Came back after lunch and swapped the carby over to using mine. Started ok, idled sort of, very little black smoke but on full throttle the revs were up and down so I adjusted the spring tension on the throttle linkage and this settled down nicely to a constant running engine at full throttle. Back it off to idle and got a back fire through the exhaust but at least it was now idling with almost no smoke but when I pulled the throttle on full and fast there is a hesitation. This to me is a mixture problem but no matter where I adjust the mixture screw it made little difference but I have found a spot where it is at the least amount. I drove the tractor up and down the drive way but this is not good enough to test it so will do a road run tomorrow and see where I am at.

I did end up with my timing light connected and managed to get the light around the engine to the inspection hole on the opposite side and reading from #1 HT lead I do not see any marks on my flywheel. The same goes on the other 3 leads, any clues on this one?

baron_beeza
Posts: 19
Joined: Sat Jun 29, 2019 1:25 pm
Location: NZ

Re: Solex-30FV

Post by baron_beeza » Mon Nov 04, 2019 6:27 am

Glad to see you are making some progress.
Now that it is running better it should makes things easier to find the last of the problem areas.

I was actually using the Cropmaster here but it was only when I developed a fuel supply issue, the other day, did I decide to drop the carb. It just started easily but would only run for 10 secs or so before conking out. Actually it started very quickly, just a few compressions each time. Before the starvation issue it would just have a limited rpm band, idle and fast idle, further movement of the throttle didn't do much.

With the carb off i found a spider in the top of the needle valve, this carb is not running a banjo bolt and gauze screen yet. That was the cause of my fuel feed problem. It was while I had it apart I noticed the locating peg for the choke tube basically doing nothing.

I saw your pics here the other day and started wondering even further. I fitted a 30-23 choke tube this morning and it started easily, ran continuously etc. The big difference now is that the throttle lever is more effective. The governor is holding the rpm all the same so it is not as though the engine is racing compared to before.

I just need to make some adjustments to the idle mixture and governor rod to get a more stable low idle now. The governor is over-riding the carb idle screw and although I have a stable and smooth idle, it is a few hundred rpm too fast.

This is a petrol only Cropmaster so I am not sure what the choke tube should be or what the other carb settings are. I will look that up later. I am only using the machine for relatively light duties so I am guessing I am like you, seeking smooth running and not necessarily max power or economy. I was using it without a key component so these things are not that fussy. You will need good vacuum though so any valve or induction leaks will upset things.

My engine was developing vacuum even without the venturi, not enough to draw max fuel through the main jet but.

User avatar
GeoffDEAL
Posts: 456
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: Solex-30FV

Post by GeoffDEAL » Mon Nov 04, 2019 8:37 am

Hi cobbadog did you try moving the distributor to get the timing mark to line up, check basics no 1 cylinder at top of compression stroke what are the valves doing and where is distributor rotor pointing. Usually DBs like more advance than they really need and its easy to loose the timing mark when moving the distributor. Do you have a older garage near that has an older Sun or Allan engine analyzer gear that it could be run on to pin point where the problem is, most garages have thrown out this gear but it works on older stuff that has points ect, originally this analyzer gear was the same price as a large car new i was told. Also is the small insulator washer under the pivot point of the points there ? and in good order. Cheers Geoff

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Mon Nov 04, 2019 10:50 am

This time I did not have the rocker cover oof when looking for the timing marks. I got the letter "M" in the middle of the opening on the bell housing, rotor button pointing at #1 position in the dizzy. The fibre washer is in between the top pivoting part of the points and the fixed bottom part and is in perfect condition to look at with no wear and is of an even thickness.
Only one garage local here that does not have a mechanic and the only mechanic locally has all modern stuff that I have seen. I should go and check him out a bit closer as he now services our cars and is always up for a chat.
I was also asked if there is an advance mechanism inside the dizzy. My initial reply was no but I will check the manual out in the morning. There is a small amount of movement back and forth on the shaft of the dizzy but for something this age and with so much adjustment plus a constant single direction rotation I couldn't see this being an issue.

User avatar
GeoffDEAL
Posts: 456
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: Solex-30FV

Post by GeoffDEAL » Mon Nov 04, 2019 8:50 pm

Hi cobbadog when you say small amount of movement in the distributor shaft would it be say half of the 0.015 points gap this can mean the points will bounce around at certain RVS and can cause eratic running, is the rotor tight on shaft, rub contact blade end on tyre rubber to clean it not abrasive as it removes metal, the contacts in cap clean them of build up, the caps can electrical track - fine lines - and will never come right, has cap been replaced. cheers Geoff

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Mon Nov 04, 2019 10:22 pm

Hi Geoff,
The amount of movement in the shaft would be enough to alter the gap/timing but if it is running in a continuous direction I think it would not alter timing and point bounce could occur if the spring tension was poor but this one is good.
I just opened up the manual and there is an exploded diagram of a dizzy but not mine. The diagram shows a dizzy with a flat section on it and I think it is a Lucas DZ4A and I think mine is a Lucas N.410525 but there is no markings on the housing to prove its make or model.
They describe an automatic timing control beneath the base plate so I will have a look to see if everything is free inside. Rotor button and brass contacts inside the cap are spotlessly clean and should be in perfect working order. Having a look in the dark might also turn up any spark tracking if any is happening.

User avatar
GeoffDEAL
Posts: 456
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: Solex-30FV

Post by GeoffDEAL » Tue Nov 05, 2019 1:28 am

Hi cobbadog its more spark scatter at certain RVS if shaft is worn see what the points do when you move it. The caps do fail with age even if they look alright and dry and tracking occurs inside the cap there are two types of rotors one has a larger contact blade not sure what difference probably more duration. Many clean the rotor blade by sanding ect this removes metal the best way is to rub it on rubber tyre this just polishes it removing electrical build up. with cap contacts just clean off electrical build up no more. Yes there are at least two different distributors later one has a flat plate under the rotor covering the points. The caps on the tractors when working were replaced as necessary to improve running. cheers Geoff

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Tue Nov 05, 2019 10:58 am

Thanks Geoff, the picture of the dizzy in my manual shows a flat section at the back of it that sticks out towards the engine block where this dizzy is round all the way with no flat spot.
We actually have been getting some good showers of rain which will help quell the bad bushfires we have had very close to us, less than 5 klms away when it started. My problem is when it rains, it leaks right where I need to stand to work on it and have not enough room to shuffle him around so did a repair job on a fuel tank from a farm pumper engine and paint it tomorrow.

User avatar
cobbadog
Posts: 648
Joined: Tue Oct 11, 2011 6:18 am
Location: beautiful Coopernook NSW. near Taree. NSW. Australia

Re: Solex-30FV

Post by cobbadog » Wed Nov 06, 2019 10:31 am

Went back to basics again today. Off with the rocker cover and checked that I was timing this on TDC and on compression and it was. Lifted the base plate out of the dizzy and found the auto advance in perfect working condition and so while I was in there I sprayed it with either and wiped the small amount of oil out of the base and then put a drop or two of engine oil on the moving parts and again down the centre shaft as suggested by the manaual. Cleaned and gapped the points to 0.012" as per specs, plugs at 0.025" as specs. Brought the engine up to the "M" mark on the flywheel and adjusted the dizzy to just break the points by using a test lamp connected to the battery and as soon as the light goes out the points have broken. Rotor facing #1 position by the lug on the body of the dizzy at #1 position.
I did take a couple of pics of this but I have not had time to load them and will do that tomorrow. Was about to do a start up and a customer came and that was the end of that for today. When you see the picture you will notice the position of the dizzy sitting in the block, the direction of the rotor button and where it is sitting facing the lug on the housing of the dizzy but something that is curious to me is that the leading tip of the rotor has passed the lug. This to me makes me feel as if the spark is too advanced and if I rotate the body then the points are sitting on the flats of the dizzy shaft a long way away from a cam lobe. Rotor turns clockwise when you see the pic.

User avatar
GeoffDEAL
Posts: 456
Joined: Tue Jan 27, 2009 8:25 am
Location: New Zealand

Re: Solex-30FV

Post by GeoffDEAL » Wed Nov 06, 2019 11:10 am

Hi cobbadog the original points gap is 0.012 however my other manual says 0.015 one person was having poor running at 0.012 and ran fine at 0.015 probably loose shaft. Interesting the rotor position will check a motor here. What plugs do you use i have always used D16 Champions without any problems i think the original were AC cant recall the number, gap was always 0.022 but close enough, cheers Geoff

baron_beeza
Posts: 19
Joined: Sat Jun 29, 2019 1:25 pm
Location: NZ

Re: Solex-30FV

Post by baron_beeza » Wed Nov 06, 2019 9:40 pm

these machines are old, components are worn. Against that we are generally talking mild mannered, almost boiler-like engines. Just some air, fuel and a spark will generally get an engine running. The degree of power, smoothness, economy etc comes down to the condition of the various systems.

I had two engines here that I had running after about 8 years of storage and no doubt years of neglect prior to that.

One distributor had so much wear in the shaft that the points couldn't be gapped correctly. Indeed no spark as they were really never closed.
Of the carbs, one was missing the choke venturi and the other was missing a plug at the bottom of the main jet chamber.

Both engines ran !

I have seen Youtube clips of proud owners and their tractors with the engines running horribly. Many were surging and almost undriveable.

If the engine is in reasonable condition, valves and rings then we should have compression and be able to draw a vacuum.
The sound of the engine on the starter motor and a hand over the air inlet can tell us all we need to know there.

The spark can be easily checked with an older type strobe light. Any misses are readily apparent.
If the engine is running rough then a simple dash of paint on the front pulley will be enough to confirm spark regularity and the advance operation. Turning the distributor by hand will get the timing in the ball park.

That leaves fuel. My current issues.

A very basic carburetor though and easily worked through.
With the leaks sorted we just need to have the float operation, idle circuit and possibly choke (air strangler) to get idle and some power.

The venturi, emulsion tube and main jet come into play for higher power settings.

I found it easy to use the Mitsubishi distributor to get both engines running. It was easy then to get the Lucas job to the same standard.

I think there will be many older tractors getting about running on completely worn out distributors and bad condensers etc.
I put electronic ignition and a new aftermarket carb on one of my BSA bikes and halved the fuel consumption. Twice as many miles on a tank of gas. Sure it did run much better but then again it was running ok beforehand.

If I can't find a replacement 30-23 choke tube for the carb I will either spin one up on the lathe or modify something that looks similar. It won't need to be a new replacement, everything else is 70 years old..

Post Reply

Who is online

Users browsing this forum: No registered users and 18 guests