The Fordson Tractor Pages Forum

hi guys any one got any ideas ,
just finished rebuild on super dexta engine full works every thing ,
fired her up she started very well no excess button or heat just on tick over
a few minutes later oil drippin from back end of engine ????????to me points to rope seal ???

but

all was renewed, any one else had this problem ?????????????
any replies very welcome/am ready to face the worst .poor wallet//,
thanks davetsdexta<<<

Sorry to say but you prognosis could well be correct. Just check silly things like the pipework oil feed up to the rockers first and the back of the rocker cover but it does sound like a strip down and check that seal.
Is the oil coming from between the back of the block and the adapter plate?
It could also be your cork seal on the sump around the mainbearing caps.
It all points to a strip down and check sorry to say.
Jerry
Bath
UK

Did you soak the rope seal in oil prior to fitting?

Gerald

Is it running down the front of the adaptor plate on the back of the engine or the back of the plate? Front is cork seal in the sump around the rear main bearing cap, the back will be the rope seal.

I'n not sure what is normally supplied for the rope seal. I used graphite impreginated rope from the engineering suppliers and did not soak it in oil, simply because I did not read that part of the manual until after it was installed, but had no problems.

Peter

I have two types of rope seal, one is a grapite coated type packing which was supplied by the local machine shop and I think it is genuine Perkins supply. The other seal supplied by Sparex is a hard white packing which I assume is to the original Fordson spec and needs to be soaked in oil.

Gerald

i have renewed mine a few months ago with the white rope seal, still leaks, guess i did it wrong or the sump gasket has a leak. its on the to do list.

regards,
John

hi guys sorry about late replies ,but could not access the site ,kept comin up server probs,
but it was a new seal (white) in a kit from sparex ,an yes it was soaked in oil prior to fitting,
an i can remember it was a little tight ,to say the least ,the cork gasket // ,ok i cut it to length but it seemed ok

you say if its comin down front of engine adaptor plate ,,it will be rope seal ,,if its the back side it,s the cork gsket,,
would it not run down the inside of adaptor plate either way as cork gasket is underneath rope seal
also do i need to take sump off ????or can it be done with sump on ,,an just split engine from bell housein again
an which rope seal do you recomend <<i don,t want the same prob again on completion?
would like to paint it as its ready for it <<

thanks you guys realy appreciate your info <<<<<davy ..........

You don't need to take the sump off to replace the rope seal, as you say just split the tractor. If I recall correctly the manual say to cut the rope seal over length, rather then flush with the housing, on the ends.

If it is the cork seal at the rear of the sump, then just the sump off, but dont forget to support the engine from above as the sump is part of the engine structure. The block may crack without support from above.

Peter

Yes, the rope seal should protrude slightly.

Time will tell if mine leaks (as its not been run yet) but, it was a white seal which I soaked over night in oil. It was actualy a bit of a sod to fit!

For all the other gaskets I have used some sealant on them so hopefuly they should be ok.

thanks guys ,,,yes as you say ,i can remember it was a sod to fit , (built up in november)
i think i had to cut a little off the ends as no matter how i tried it would not fit in <<
do you think this is ,,,or could be wrong,,,i would like to know now if poss before i pull her to bits again ,,
then i know it won,t happen next time,, hopefully ,,
an whitch type of rope seal is best ,,or where best to get it from ???????????
do you have to buy the full bottom gasket kit .or can you buy just the dits you need .
thanks again ....frustrated ,,,,,,,davysdexta,,,,,,,,,

If I remember there was an article in Tractor and Machinery magazine last year covering the fitting of the rope seal (it was covering the rebuild of a MF35 engine but this area is the same). It showed the use of dies to force the seals into the caps.
When I fitted my seals last year I didn't have the dies but resorted to using a piece of round steel just smaller than the shaft diameter and forced the seal (after it had been soaked) in starting from the centre and working towards the ends. You have to have some seal protruding at the end. I managed to cut the ends using feeler gauge strips to give me the thickness and cutting using a large scalpel blade. You can't get a clean cut as the rope fibres fray out but I seemed to work OK and so far no leaks (touch wood!!!!!)

Jerry
Bath
UK

I noticed after fitting mine that it was tight against the crank and made the crank very stiff to turn (this was before inserting the pistons which add significantly to the drag with new rings and honed bores).

Hi when i rebuilt my engine the rope seal was soaked
overnight , and then when putting it into grove i put the ends in first
leaveing a slight bit about 1/8 protuding , this left the rest bulging
in the middle , ithen was able to work this in
working from middle out . This worked well for me.
GERRY

mark .as u say mine was the same very tight to turn when in place and tightened up (just crank on its own )
hope it has nt,dried out standing and picked up some when started up,??????????
as been stuck to crank that is ,,,but i will let u all know next wk when i get her appart again ..
thanks again,,if any one thinks of anythin else please let me know //
davy,,,
soon to be painted I HOPE????

i have been told to wipe some grease across the rope seal to help seal it

Regards
John

hi again guys as promised just to let you know .the problem was the cork gasket ,,
must of been when sump was placed on .it has picked up last piece of cork gasket (about half an inch )
an torn it off,,actually came out when oil drained off , awaiting new gaskets ,will watch more this time round,
dont want same thing again ??????? hope this helps others when placein sump on ,backend o crank behind rope seal,,,
davysdexta,,,

I split my dexta last night, and looks like i fixed the rope seal last time but the sump gasket seems to be leaking. can i just go round the bearing cap with some form of sealent or can do i need to remove the sump? how do i remove the sump? i have no engine hoist to lift the engine to remove the sump. can i put the engine back in and then remove the sump, or will there be any damage to the engine?

Regards,
John

john
hiya i took my engine out because i did.nt know wether it was seal or cork gasket ,
wonse i new it was cork gasket ,,u could actually see where it was missin at close inspection,
ithought the same as u can i seal it with anythin ,,,then thought do it properly its a lot o work for it to go wrong again
so while it was up on lifter ,oil drained of ,then i laid it down on side .bein carefull not to damageany thing (using wooden blocks)
lifting sump end higher than head end an took sump off ,,after makin safe with chocks,
dont forget the two nuts that is in like a recess .,an lifted clear after tapping gently to free it ,lift off squarely not to bend oil pickup
good luck,i,m waitin for new gaskets ,,,i hope fri then i,m gointo build it up again and put back in
let u no how i get on ??????????
cheers davy //////////

i was planning to lay the engine on its side but i have no hoist so could end up dropping it and not being able to pick it back up.
i have tryed the sealent today. if it works, great. if i dosent then ill have to fix it properly.

Regards,
John

hi john
let us know if the sealant works . hope it does ,,,if not another LOT of work???????
davy,,

Hello everybody, I am just new member of this forum, and I come from a small farm in Norway. I have repaired at several Dexta engines, and have experience,d that it is (on this over fifty years beautys), ...leaking oil from at least three mainpoint underneeth the engine. It can be from the corkseal in front, from the corkseal in rear of the engine, (booth this must be changed while the oil-pan is of), and yes, mybe the most important is the ropeseal behaind the adaptorplat, I recomend to mount the oilpan with new gasket,s and new corkseals very accurate befor the adapterplate comes on...and so I do som test of how the rope seal will fit, and dipped in oil, it will tell this, (when the two half cover is try to press the ropeseal on place). -I also sometimes use two bolts who are alitle longer to press the two halfcover,s with the ropseal,s until all the screw,s fit good. -the cork-seal,s and rope seal is alitle longer so therfor is the test neccesery for cutting this alitle "overlengt"
-It is also very safe to change the sim fom the gearshaft in front of the gearbox too. After this overhaul, you can have a dry dexta for many year.
-At least...mybee the leak can be stopped from changing only the ropeseal, but it is a lot of work to separate engine fom tractors, and at so old tractors as this, I also do the check on my clutch. In the clutchsystem (it is also some small bolts from the clutch-release part,s who has some damages after many year,s), so if this thing is checked up in the same procedure, you can sleep well after necessery repaires then.

from Mikkel.

Think i fixed my dexta's leak! My attempt with sealent round the rear of the sump failed. in the end i found it quite quick and easy to drop the sump. removed radiator and front axle, then put a jack under the sump removed the bolts. worst part of the whole job was breaking the seal between the block and sump. provided a good chance to clean out any deposits from the sump. To refit the sump I used instant gasket. seems to have held up well after an hours mowing. hopefully it will hold.

Regards,
John

hi john
good to know you have got it done ,and hopefully fixed for good
did you change the cork gaskets at each end of sump ,,,,,,,,,,,
or just use instant gasket on top of old cork ones ,,,,,
i have.nt had mine runnin yet since re,newin gaskets .due to been away
hope to start her later this week ,,, fingers crossed ,,,
davy

the cork was well past it. made a thick layer of instant gasket up where the cork should go. seems to be working. i had the pannel off the base of the sump and working through that, wiped a bit more gasket on anywhere that looked like it didnt seal 100% on the inside.

Regards,
John