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TD42 Rebuild

Posted: 21 Jul 2017 12:28
by Rudolph
Afternoon All

My TD42 head-gasket developed a problem, and we started to take the engine apart. It looks like the engine overheated at some point in the past, but in general it does not look to bad. Measured up the cylinder bores (liners inner diameter) this morning 96.1mm and 96.2mm and it is oval by 8 thou, engineering shop measured it up. The manual that I have shows that the diameters should be 96.01-96.02mm for grade 2. The pistons that came out has a C2 marking on, I assume that is grade 2 pistons according to manual, the piston pin small end is 28mm. We will need to put new liners and pistons, where can the liners be sourced, does the liners and pistons come in kit form or separate?

The engineering shop is busy recon the head, as shown in the pictures do we need to worry about the pre-combustion chambers markings/cracks and replace them or leave as is, how do we know if replacement is required? The engineering shop want to replace them. Any comments/advice on this will great.

At the same time we will also put in a new clutch kit.

Re: TD42 Rebuild

Posted: 21 Jul 2017 12:50
by iandvl
Rudolph - this is something Michael will be able to answer. I believe he is *the* go-to-man for the TD42...

Re: TD42 Rebuild

Posted: 21 Jul 2017 12:57
by Michael
Rudolph

Good call to strip the engine and make sure everything is ok.

C2 is the piston grade number but makes no difference if it is going to be changed.
I will change the combustion chambers if it was my call, just buy everything you need from Alert. Ask for TD27 combustion chambers and pistons.

If you are considering turbo charging the engine at a later stage I will recommend getting turbo pistons so you know that the internals are up for the job. I would actually just out in turbo pistons as they can tolerate more heat than the NA pistons and believe me when I say that the NA engine can easily have higher combustion temps than a turbo engine.
the down side is that there are no turbo pistons available for the 28mm pin so you either have to resize the conrods or just stay with NA pistons.

Now with the sleeves you have a couple of options. You can either keep the current ones as is and just have the block bored one size up and get oversize pistons. (this will be the cheapest)
Another option is to get semi finish sleeves that can be bored to the correct size. this is preferred by me as they are cast iron sleeves and are very strong.
Last option is to get a sleeve kit and have that put in, these are quite scarce and you will not find it easily.

keep us posted on the build :thumbup:

Re: TD42 Rebuild

Posted: 21 Jul 2017 13:14
by Dustin
Sorry to hear about the drama, but on the up side it's all apart so now you can throw some TD27 turbo pistons in for the turbo conversion.

Re: TD42 Rebuild

Posted: 21 Jul 2017 13:32
by Rudolph
Dustin wrote:throw some TD27 turbo pistons in for the turbo conversion.
I'm definitely going the "Michael bolt on" turbo route, so will be putting in the TD27T pistons.
Michael wrote:Another option is to get semi finish sleeves that can be bored to the correct size. this is preferred by me as they are cast iron sleeves and are very strong.
Michael do we also source these semi finished sleeves from Alert? What do I ask for? Can you assist me on this please?

Will keep you posted.

Re: TD42 Rebuild

Posted: 21 Jul 2017 15:07
by Tinus lotz
Nice .....maak hom sterk ....jy het deftentief een van daai silwertop motors. ....hulle het almal sover 28mm conrods gehad ......imho resize mater jy wil turbo pistons hê :blonde:

Re: TD42 Rebuild

Posted: 21 Jul 2017 15:15
by Rudolph
Tinus lotz wrote:imho resize mater jy wil turbo pistons hê
Dankie Tinus, jy praat nou van die conrod resize van 28mm na 30mm?

Re: TD42 Rebuild

Posted: 21 Jul 2017 15:56
by ricster
You are going down the right path.... TD27 precoms fit exactly as do many other parts. Master Parts in Cape Town can also assist with this ( speak to Dean ). Not sure if there is a branch in Port Alfred though, but check prices and maybe they can courier it to you.

The small cracks in the precoms is normal, so don't stress about that, but better to replace while the motor is open anyway and they are very cheap... probably only about R70-80 each. Put them in the freezer for a few hours and leave the head at room temp. They will slot in and expand as they defrost

Re: TD42 Rebuild

Posted: 21 Jul 2017 16:54
by Michael
Rudolph, here is a pic of the sleeves I use. They are quite afordable. Just remember they are .020 oversize on the OD so the block just need to be machined to get them in. But the engineers will know exactly what to do

Re: TD42 Rebuild

Posted: 21 Jul 2017 19:22
by Rudolph
Thanks Michael! Appreciated, just a pitty you so far away, but the up side is this great forum!