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Engine rebuild.

Posted: Fri Dec 14, 2018 12:21 pm
by Mervyn Spencer
Hi, I have removed the engine head and it is currently been overhauled. I took the injectors to be checked over and found that the one needle was pitted, so all three were replaced and injectors serviced. On examining the pistons and cylinders I noticed on piston one and two there were round impressions in the soot on the piston which could be the result of gasses escaping from under the valves. On examining the sleeves number 1and 2 have moderate wear, but number 3 the wear is almost if not 1mm deep. So unfortunately the engine has to go to the engineers as I do not have the equipment to do the overhaul. This exercise will have to wait for the 2019.
Cheers.

Re: Engine rebuild.

Posted: Fri Dec 14, 2018 11:35 pm
by kiwiland dexta
Be good to keep up with your progress, Mervyn, given the amount of gas from my breather I would like to do the same and fix the several leaking seals at the same time!
Remember the picture too!

Re: Engine rebuild.

Posted: Sat Dec 15, 2018 9:28 am
by charlie63
Mervyn,
Not so good you are having to get the engine rebuilt. On the other hand it will last many years to come again. Keep us posted on the progress. Just a pity you dont live close by or I would have offered to do the job for you.

Regards
Charlie.

Re: Engine rebuild.

Posted: Sun Dec 16, 2018 8:54 am
by Mervyn Spencer
Kiwiland, if it is a working beast then it might be one of those unfortunate chores :( . I need to refresh my grey matter about attaching pictures, one of those talents I don't possess.

Charlie, I will certainly keep you abreast with progress. Thank you very much for your thought on possibly helping me, maybe we can meet halfway in Angola :lol:.

I have been cautioned on attempting to remove the engine whilst the tractor is without rear wheels and on stands. The rear end is been supported by stands under the lower link arms bolt. My rear wheels have not been complete with painting and assembled yet.

Re: Engine rebuild.

Posted: Sun Dec 16, 2018 9:21 am
by charlie63
Mervyn,

I use postimages.org now for all my photographs since the carry on with photobucket. It is very user friendly and free and you can resize your photographs as you upload them and then it also gives you the option for downloading to forums.
With regards to removing your engine whilst the tractor is on stands. Since you already have it supported under the lift arm fixings you will need to support it under the gearbox too to be able to remove the engine as you will split the engine from the gearbox bell housing.

Regards
Charlie

Re: Engine rebuild.

Posted: Sun Dec 16, 2018 7:41 pm
by Mervyn Spencer
Hi Charlie,

Thank you for the heads up, I did try Postimage now and noticed that I had used it before to post an image of my lift pump. I had to request a new password though. Firstly, how do I change their new password to my own simpler one? I will take a snap of my head in the morning and try posting it.

Again thanks for the advice on having a support under the gear box as well, good plan.

Re: Engine rebuild.

Posted: Mon Dec 17, 2018 5:43 pm
by Jerry Coles
Hi Mervyn
When you have rebuilt your engine and have got it installed and ready for use then it needs to be worked hard so that the rings can bed in and seal properly. When I rebuilt my engine 10 years ago I used it on it's first time out for topping. It never missed a beat and has remained faithful to me ever since. It uses little oil, starts very easily and is very responsive. BTW never use products like "Easy start" as these can let get into the combustion chamber and wash away the oil around the rings and can cause early engine failure. Tip. When you are ready to mate the engine with the gearbox I used long threaded rod fitted into two holes on each side of the engine to help align the block to the gearbox. Once you have it close (and the gearbox shaft entered into the flywheel!) then you can undo the nuts and remove the bolts for the final inch.
Cheers Jerry

Re: Engine rebuild.

Posted: Tue Dec 18, 2018 9:40 am
by Mervyn Spencer
Hi Jerry,
Thank you for your valuable advice about running the tractor hard after the rebuild. Yes I'm aware of that nasty spray and what damage it can do. This will be the second time round that I will be splitting the tractor, after I bought the Dexta in 2004 I had to have the clutch replaced and don't understand why I did not get the engine done up as well at the same time. Those extender bolts that you are referring too were such a great help then to guide the engine against the bell housing, I still have them in my set of tools. I found that last inch you refer to is a blighter to get closed been very caution of not damaging the clutch. Any way I appreciate your input Jerry, Charlie and Kiwiland, thank you.
Mervyn.

Re: Engine rebuild.

Posted: Thu Dec 20, 2018 12:48 pm
by Mervyn Spencer
Image

Image

Image

Image

Re: Engine rebuild.

Posted: Thu Dec 20, 2018 12:53 pm
by Mervyn Spencer
Okay I managed to post my pictures of the pistons and sleeve, how I don't know. I will need to go back step by step :wink: .
So that is what I was presented with when I took the head off. How is all that muck in the galleries get cleaned up?
Mervyn

Re: Engine rebuild.

Posted: Mon Dec 31, 2018 8:23 pm
by Nick
Hi Mervyn,

Are you sure the liner is worn that much? Could it be carbon build up instead? If you have some emery paper, give it a clean up, you never know you may be lucky!

Re: Engine rebuild.

Posted: Mon Jan 14, 2019 9:01 pm
by Mervyn Spencer
Hi Nick,
Sorry for the delay in getting back to you. I tried today to see if the ridge in the no 3 cylinder was carbon, but definitely metal. not serious I have no option but to have the engine rebuilt. could the damage not be a broken top oil control ring gouging(sp) into the sleeve? Unfortunately no further progress made due to health issues.

Re: Engine rebuild.

Posted: Tue Jan 15, 2019 9:38 am
by Mervyn Spencer
Off to pick up my tractor head, had new valves fitted.

Re: Engine rebuild.

Posted: Tue Jan 15, 2019 6:40 pm
by mathias1
Mervyn Spencer wrote:Off to pick up my tractor head, had new valves fitted.
Also new valve seals? Dont' forget to check the clearance on the valves before starting the engine!

Re: Engine rebuild.

Posted: Tue Jan 15, 2019 9:12 pm
by Mervyn Spencer
Thanks Mathias for the heads up, the engineers that did the job for me have been around a long time and I trust that all is well. You refer to valve seals Mathias, not sure what you are referring to as nothing is mentioned in the parts list or workshop manual, are you possibly referring to the valve guides? According to the engineers they felt only the valves needed replacing.
According to the job sheet the following was carried out: Reface valves, reface valve seats and grind in and assemble valves.
I still have a long way to go so will definitely check valve clearance before starting the tractor.
I have been watching a very good series of a MF 135 engine rebuild on You Tube by Bundy Bear down in Queensland Australia. He has a tractor repair business, what a knowledgeable man.

Mervyn.

Re: Engine rebuild.

Posted: Tue Jan 15, 2019 11:02 pm
by mathias1
Mervyn,

I don't know the dexta engine that well, so it's possible there are no seals there.
such seals do prevent the engine burning oil.

Re: Engine rebuild.

Posted: Thu Jan 17, 2019 1:54 pm
by Mervyn Spencer
Hi Mathias,

I don't believe valve seals were fitted to the Dexta or 3-144 and 3-152 engines, I have looked at numerous tractor parts suppliers and my parts manual and no seals are listed. Do the major valves have seals?
Thank you again for your interest and the heads up.

Mervyn.

Re: Engine rebuild.

Posted: Fri Jan 18, 2019 12:52 am
by mathias1
Mervyn Spencer wrote:Hi Mathias,

I don't believe valve seals were fitted to the Dexta or 3-144 and 3-152 engines, I have looked at numerous tractor parts suppliers and my parts manual and no seals are listed. Do the major valves have seals?
Thank you again for your interest and the heads up.

Mervyn.
yes they are on a major.

Re: Engine rebuild.

Posted: Sun Jan 20, 2019 7:54 am
by Mervyn Spencer
I'm amazed, but thank you for confirming that point to me.
Whilst on the subject of the head, I have noticed that my rockers are kind of worn, can one have them resurfaced or do you have to replace them? Just a reminder that this tractor is a toy in my eyes, not going to do any hard work whilst in my procession.

Mervyn.

Re: Engine rebuild.

Posted: Sun Jan 20, 2019 8:03 pm
by Mervyn Spencer
Image
Image

Pictures of Rockers as per my earlier post.

Re: Engine rebuild.

Posted: Tue Jan 22, 2019 8:29 pm
by Mervyn Spencer
Report back on my rockers for those that are interested. Took them to the engineers and they ground off the burs and now looking good. :clap:

Mervyn.

Re: Engine rebuild.

Posted: Thu Mar 14, 2019 6:38 pm
by Mervyn Spencer
I was cautioned to have my rear wheels fitted before I attempt to remove the engine, today I eventually finished painting my rims and centre disks. Unfortunately I will have to wait a couple of weeks before I assemble the disks to the rims, I used synthetic enamel paint which takes awhile to dry out. Once I have the wheels fitted I shall commence removing the engine and get it to the engineers.

Mervyn.

Re: Engine rebuild.

Posted: Sun Mar 31, 2019 11:55 am
by Mervyn Spencer
Hi there again, sorry taken some time to add the odd bit of progress. I eventually got around to spray painting my rear wheel rims and centre disks. Whilst waiting for the paint to cure I started removing various items from the engine block i.e. radiator, generator(dynamo),fuel pump, fuel filter and oil filter. Lastly was the starter motor, but sad to say I noticed the pinion is rather worn in places :cry: . The part number is E93CQ9, which were fitted to the Majors and dextas. I did make some inquiries at a couple of dealers but they want to sell me a new motor :shock: .I can see this tractor sinking my bank account.
Whilst fitting the centre disks to the rims I noticed air escaping around the valve stem of the right hand wheel :curse:, so that's another issue. As soon as I have the puncture repaired and wheel fitted I shall attempt to remove the engine block. Obviously before I can do that the front axle needs to come off. Wish me luck.

Re: Engine rebuild.

Posted: Sun Mar 31, 2019 1:38 pm
by mathias1
Mervyn Spencer wrote:Hi there again, sorry taken some time to add the odd bit of progress. I eventually got around to spray painting my rear wheel rims and centre disks. Whilst waiting for the paint to cure I started removing various items from the engine block i.e. radiator, generator(dynamo),fuel pump, fuel filter and oil filter. Lastly was the starter motor, but sad to say I noticed the pinion is rather worn in places :cry: . The part number is E93CQ9, which were fitted to the Majors and dextas. I did make some inquiries at a couple of dealers but they want to sell me a new motor :shock: .I can see this tractor sinking my bank account.
Whilst fitting the centre disks to the rims I noticed air escaping around the valve stem of the right hand wheel :curse:, so that's another issue. As soon as I have the puncture repaired and wheel fitted I shall attempt to remove the engine block. Obviously before I can do that the front axle needs to come off. Wish me luck.
Mervyn,

first check if the tyre valve is alright. I've got a bad tyre this weekend, and after a lot of work to get the tyre off, I found the problem at the valve...

Re: Engine rebuild.

Posted: Mon Apr 01, 2019 8:50 pm
by Mervyn Spencer
Hi Mathias, thanks for your response, been there did that even put some oil on the "O" ring. It turned out that there was a couple of sharp surfaces on the rim which damaged the tube, there were about 6 tiny ruptures so grinded the rough stuff off and fitted a new tube. The frustrating issue is that I had painted my wheels all smart all for the rim to be chipped when the tyre had to come off and then be replaced :cry:
Anyway when I got home I tidied all the damage up and ready to repaint on Wednesday, nice hot day. :)