Land rovers haven't changed much in 40 years - DI 2.25 anyone???

Printable View

Show 40 post(s) from this thread on one page

17th August 2011, 05:23 PM
PAT303

So all this because you don't want a timming belt or because you have the bits and want to see if it works?. Pat
17th August 2011, 07:34 PM
JDNSW

Quote:

Originally Posted by isuzurover

Yes, thanks, I had a typo in my post - fixed now. I was attempting to say the same thing. My old LR mags mainly talk about cam issues with the TD. However a bit of digging reveals 2 main failures:

Heads and piston cracks, followed by cam wear and block cracking (though this seems less common).
.......
Since I wouldn't be using the head or pistons, and the cam will remain 2.25D, that may increase reliability...?

The block cracking was the bit that rang alarm bells for me, as this is the bit that you are planning on using. Did you find anything about where the block was cracking? Was it due to insufficient strength somewhere or due to a cooling problem?

Cam wear seems to me to be unusual, as I assume this engine has roller cam followers the same as the earlier versions, and this should mean that cam wear would be the result of lubrication failure, possibly poor maintenance. Or manufacturing defects - I can remember when I worked for a company where I had a company car, I was talking to the fleet manager one day, and he had on his desk a Falcon camshaft - with half the cams worn almost round - at 2,000km! Faulty heat treatment.

John
17th August 2011, 10:55 PM
Veryan

It sounded to me as though Ben was not going to turbo the engine...although I could be wrong
17th August 2011, 11:42 PM
isuzurover

Quote:

Originally Posted by PAT303

So all this because you don't want a timming belt or because you have the bits and want to see if it works?. Pat

A little from column A, a little from column B.

Quote:

Originally Posted by Veryan

It sounded to me as though Ben was not going to turbo the engine...although I could be wrong

Not sure yet. It will certainly be NA at the start

Quote:

Originally Posted by JDNSW

The block cracking was the bit that rang alarm bells for me, as this is the bit that you are planning on using. Did you find anything about where the block was cracking? Was it due to insufficient strength somewhere or due to a cooling problem?

Cam wear seems to me to be unusual, as I assume this engine has roller cam followers the same as the earlier versions, and this should mean that cam wear would be the result of lubrication failure, possibly poor maintenance. Or manufacturing defects - I can remember when I worked for a company where I had a company car, I was talking to the fleet manager one day, and he had on his desk a Falcon camshaft - with half the cams worn almost round - at 2,000km! Faulty heat treatment.

John

Not sure yet - need to search some more. There was a block revision part way through 2.5TD production which fixed the cracking issue apparently.

IRC the cam issue I read about previously was because the cam bearings were pressed in from the front, so the rearmost bearing was pressed through a few journals, and would become loose. It would then drift and block the rear oil gallery. That may be a load of LRO BS however as I haven't come across that specific explanation recently.
22nd August 2011, 12:00 PM
isuzurover

Anyone have a broken TD5 or a TD5 piston handy???

Quote:

Originally Posted by isuzurover

Can someone with parts lying around please measure:
(1) Gudgeon pin diameter and (2) gudgeon centre to piston crown, for:

B. TD5 Piston
22nd August 2011, 12:29 PM
roverrescue

Ben I have a set of 300 pistons STD size that you could use in the project?
Will prob need a set of rings for them and unfortunately the gudgeons have been very handily used on the 30T press as accessories so wont be much use!

So what does the 2.25 use for timing? Chain I presume? Would it be feasible to retro the timing gear to a 300 block?

S
22nd August 2011, 12:36 PM
isuzurover

Quote:

Originally Posted by roverrescue

Ben I have a set of 300 pistons STD size that you could use in the project?
Will prob need a set of rings for them and unfortunately the gudgeons have been very handily used on the 30T press as accessories so wont be much use!

So what does the 2.25 use for timing? Chain I presume? Would it be feasible to retro the timing gear to a 300 block?

S

Thanks Steve!

If I use my existing block I would buy a set of 0.040" oversize 300Tdi pistons. They are ~$250 delivered from paddocks.

The chances of finding a 2.25 block with standard size bores that are in good nick would be virtually nil - sleeving would be $$$, so I don't think I would be able to use your pistons - but thanks for the offer!

The 2.25 has a chain. However the IP is driven from the middle of the cam (where the distributor sits on a petrol). So you could possibly graft the timing gear onto a 300 block, but you would have no pump drive.

I am toying with the idea of boring a block right out to fit TD5 pistons if it is humanly possible. I suspect the bores may be a bit thin... ;) But what the hell...
26th August 2011, 07:31 PM
roverrescue

Ben,

Last year when I was playing with the current fender rebuild (which keeps getting pushed back by other jobs - like 6pot volvos blowing sumps in big plateys!!!!) I was looking at the 2.8L bored and stroked MD Engineering 300tdi kit.

Anyways, I had a bare block at Myers Engines in Cairns. Josh waved his majik wand and was a little hesitant to bore her out the requesite 80 thou for the kit. He was happy to go 40thou pistons. This was on a dusted block that went from STD pistons to 40s in one hit - it had the same amount as slop as my current block. The MD 2.8 kit uses 80 thou (2mm) oversize pistons. Josh was hesitant to go that hard???? What dims are Td5 pots compared with old skool 2.25/200/300?

S
27th August 2011, 03:36 PM
isuzurover

Quote:

Originally Posted by roverrescue

Ben,

Last year when I was playing with the current fender rebuild (which keeps getting pushed back by other jobs - like 6pot volvos blowing sumps in big plateys!!!!) I was looking at the 2.8L bored and stroked MD Engineering 300tdi kit.

Anyways, I had a bare block at Myers Engines in Cairns. Josh waved his majik wand and was a little hesitant to bore her out the requesite 80 thou for the kit. He was happy to go 40thou pistons. This was on a dusted block that went from STD pistons to 40s in one hit - it had the same amount as slop as my current block. The MD 2.8 kit uses 80 thou (2mm) oversize pistons. Josh was hesitant to go that hard???? What dims are Td5 pots compared with old skool 2.25/200/300?

S

Hi Steve.

Factory pistons for a 2.25 were available in sizes up to 0.040" oversize, but 0.060" and 0.080" were also available aftermarket.

TD5 pistons would be ~0.119" oversize! About a 1 mm smaller than the diameter of an oem sleeve.
10th September 2011, 06:12 PM
Psimpson7

Quote:

Originally Posted by isuzurover

Anyone have a broken TD5 or a TD5 piston handy???

Hey Ben,

Sorry it took me so long but

1. 30mm diamater of gudgeon pin
2. 48mm as near as I can tell, maybe a fraction under between crown and centre of gp.

I may have one you can have with gudgeon pin if you want to mess about with

Quote:

Originally Posted by isuzurover

However... another consideration - Td5 pistons are 94 mm. That is 139 thou oversize!!!

Just to add, the diamater of a td5 piston is 84.5mm

cheers
Pete

Show 40 post(s) from this thread on one page