pre heater plug

wee blue tractor fan · Sun May 03, 2009 11:48 am

being new to the forum i have spent the last few days browsing and see that some people have changed the glowplug to the newer type fitted to modern perkins engines
after rebuilding my dextas engine iwas dissapointed by its cold starting ability finding it would start instantly if you put a blow torch at the inlet manifold i then took a new style glow plug and tried that to find it will start first time i connected the primer to this and it worked but the primer was leaking so i have fitted a banjo were you would bleed the air out the filter housing and it works perfectly but this leaves me with a couple of questions
could i have connected to the return line from the leak off
could i replace the leaking tap/primer with a tap off a major
any thoughts would be appreciated

aldo · Post by **aldo** » Sun May 03, 2009 1:59 pm

Everyone seems to have the same problem. I still haven't solved it - I tried the return line from the injectors leak off, but found that I get very little if any leak off! You may have read that getting the fuel from the filter is not recommended because of the higher pressure, but then that would depend on how much pressure the new glowplugs with the built in fuel line can handle (an inline tap would be advisable, so long as you remember to turn the tap off every time. Also you need a small inline reservoir to hold the fuel for the next start). I mostly solved my problem by overhauling the starter motor with new brushes, and new battery - the strong cranking power gets it fired up easily with no glowplug. Next I'm going to try extending the leak off return line down into the fuel tank, and putting in a small manual pump inline from there to the glowplug, no inline reservoir needed.

GERRY · Post by **GERRY** » Sun May 03, 2009 3:20 pm

The way i have connected mine up is with a 28mm copper pipe fitting reduced to 6mm and then a few coils in the 6mm before in goes into the new type heater plug. The 28mm fitting is connect up to battery back plate. i jjust top this up with fuel every now and a gain and it works every time .ijust hold heater button for about 10 seconds and press starter lever and it fires up . No need to connect into pipping at all. GERRY

aldo · Post by **aldo** » Mon May 04, 2009 9:09 am

Sounds good Gerry. I've being using a syringe to top up the line when I needed the glow start.

crofter · Post by **crofter** » Tue May 05, 2009 9:22 pm

Hi, I used a resovouir from MF 35 / 135 and joined to the return pipe to the fuel tank this seems to work ok.
Regards,
Ronnie.

Post by **Brian** » Wed May 06, 2009 12:21 am

A filter from a central heating system is just about perfect and looks right too. Tapped into the return line it should keep topped up.

JC · Post by JC » Wed May 06, 2009 7:00 am

I know less about Dextas than Majors, so I may be speaking out of turn, but I just looked at Agriline's web site, and they sell a fuel tap w/primer for a Dexta. Wouldn't that be the best way to go?

Post by **Brian** » Wed May 06, 2009 7:33 am

That would be certainly JC. Problem is it won't work well with the later plug which opens automatically.

Other problem is cost, you could nearly buy a Dexta for the cost

and they have been notoriously unreliable, leaking and failing within a couple of weeks.

I understand that the later ones are better but they do have a bad reputation.

alang · Post by **alang** » Thu May 07, 2009 5:50 pm

As someone who fitted a new Primer Pump system, but did not find it answered the starting problem without creating other problems (see my earlier post “Primer Pump Problem”. I'm very interested in the 'automatic fuel/heat plug" mod, but I’m a bit confused as to what’s what

. For example earlier posts talk about a 'Ferguson' type heater which injects diesel automatically. However, my late model TEF-20 does not have such a system. Is it perhaps a MF35 Perkins P3 heater? How does it operate?

By consensus are you experienced heater plug members able, between you, to bring all the good ideas into one definitive modification and describe it simply (Part Numbers/Suppliers and engineering tasks etc.,)?

Cheers
Alan

Post by **Brian** » Thu May 07, 2009 6:08 pm

Alan,
There is a thermostatic valve in the heater unit.

Diesel is held in a reservoir connected to the heater unit. When the heater heats, the valve opens and allows diesel to bleed onto the hot element and this then ignites.

JC · Post by JC » Thu May 07, 2009 7:53 pm

Brian,
Now that you mention it, I remember reading some posts about the poor quality of the aftermarket primers. When I get back to working on my Dexta (after my wife heals up from her back surgery, and after the house is remodeled

), I would like to use the original type primer and heater plug. The one that's on it now may be OK. I bought the tractor in the summer and it didn't need it to start then. Now its in the shop, in pieces.
Where can I buy a heater plug with a thermostatic valve in it? I don't want one for my Fordsons, but it sounds like a good idea for some of the other diesel engines that I have.

terry274 · Post by **terry274** » Fri May 08, 2009 12:15 am

I replaced the tap on my Dexta and was very disappointed in the quality. I had to take the valve out of the new tap and smooth the surface to get it to seal and shut the fuel off. The tap feels cheaply made when you open and shut the fuel supply.
Terry

Post by **Brian** » Fri May 08, 2009 12:44 am

J-C,

John Deere, Ford, Case-New-Holland and MF all used them in later tractors.

The Ford ones fitted in the inlet manifold, just after the rubber pipe connecting to the air cleaner, diesel came from the injector leak off pipe and from the automatic bleed system on the injection pump through a very small holed banjo bolt. They were optional on the 6X and some of the 6Y series but became standard fitting here in the early 1970's.

The other answer to your primer pump problems is to buy a PETROL Dexta!

JC · Post by JC » Fri May 08, 2009 6:06 am

They must not have been used much here. I don't recall ever seeing one on a tractor, except for Perkins-powered MFs, and they weren't in working order.

P.S. I'd like to find a petrol Dexta, but I don't think my chances are very good here.