new crankshaft or new engine??

[fatforbes]

new to the forum so hello!

I've got a p reg 300tdi 90 which i've been having engine troubles with. I recently discovered that the woodruff keyway has worn away on the crankshaft timing gear, I can move it around the shaft about 3mm. So i think I'm going to either have to replace the crankshaft along with the shells etc... Or I can just go and buy a decent second hand engine and chuck that straight in. I cant really afford a recon block at the moment, well not one from Turners which is where I was advised to go. Is it worth replacing the crank or could I end up causing more problems than i had to begin with? The engine has only just done 100k so I was intending to keep it minimal and just do the crank rather than replace the pistons and rings etc.. is this wise?? A decent 2nd hand engine seems to be about 600 quid (unless anyone knows better???). my 90 is and ex MOD used on the firing ranges so It has probably been raked so I dont know if replacing the crank will be the end of the problems

any advice is appreciated

[gruntus]

Hi Forbes,

Tough call, if you go down the road of changing the crank and the have other things go wrong you will feel really bad and you could also end up throwing good money after bad.

If you buy a new lump (advise to hear it running first) however you will have all the ancilaries you need and possibly a good supply of spares for the future.

Personally I would go for a new lump as long as its in good condition (if you dont know about engines take someone with you who knows).

HTH

Cheers

Grant

[Megansfolly]

i bought a 200tdi in the summer that not had the buttom pulley bolt done up tight enough so it ripped the key way out of the crank it has also bent the end of the crank slightly so is beyoud welding

but i am told that if u make up a bronze key and place in the key way and pool a good weld in around it the pop key out and sand weld down so it flush it should be ok.

mine is beyond welding as it badly scored where it been runn for quite some time with out the key

so i have a new crank out of my old 2.5nad that will be dropped in with new seals and shells which i am hoping is relitively easy

[Megansfolly]

some other pics

[Milemarker Type S]

As a quick fix that may see some more life out of your existing engine... Fill the hole and the inside of the pulley with chemical metal, assemble and do it up very very tight... Then leave for a day or so to set and he presto... I was sceptical until I did it on my old 2.5 NA... worked a treat and is still going some 2 years on!

[fatforbes]

thanks for all the replies. Well as you can just about see in the pic,im no photographer! , I've used that liquid metal stuff before on the outer key(left hand side of the pulley keyway on the shaft) and it worked a treat. But the damage on the inner one isn't as severe so i don't think I could get as much in the gap. Also, the reason why Ive got my engine out is because I'm rebuilding on a galv chassis with the idea that I should have a good solid landy for years and years. So i'm a bit disinclined to do a temporary fix, although it will give me another few years out of this engine for not much moneys. But if I get a replacement crank or engine it will save me time in the long run. I have no idea what the best option is

[draper40]

I had this problem on the 200tdi i was rebuiklding. I just cleanied it out and then filled it with weld before then using a mini dremel type thing to create a new hole.

Pete

[Diff]

I agree with draper40. If the engine is otherwise good, I wouldn't hesitate to repair it rather than rebuild or replace. The key itself doesn't take any appreciable load providing that the pulley is torqued up correctly. Its primary function is the location of the pulleys to maintain the timing, typically when the front pulley is off for timing belt replacement.

I would either use chemical metal (eg JB Weld) to fix the keyway with a new key, or weld it up. My preference would be to weld up the keyway damage and fit a new key. I have welded crank noses and keyways on several different engines and just carefully dressed the key and shaft with files and emery paper. The engine will run fine. Obviously the 'best' course of action if cost isn't an issue, would be to replace the engine or crank.

I would only replace it if the rest of the engine had other issues which needed addressing. As you have already found, your previous repair on the other keyway has been fine with no issues. If you repair carefully and the bolt is torqued correctly, there is no reason why it should ever give a problem.

Regards,

Diff

[fatforbes]

well I went out and bought 2 tubes of epoxy putty today and I'm going to have a go at it tonight. As you say it worked before so it should do the trick this time and if it doesn't I havn't really lost anything. And if the putty does fail then I can always have a go with the welder, although I only have an Arc welder and oxy/acetylene, kind of job that a MIG would be useful for. Could I braze it or would it not have the strength?

Just want to say I've been on other landy forums and none have been half as helpful as this one!

[townsend]

you cant mig, gas or arc weld it. the crank is case hardened steel. as you are attempting to weld different metal types would sugest tig as this is the hottest and most controllable type of welding as you can concentrate on the crank more than the pulley or woodruff key allowing it to penetrate enough. i have welded similar metal types on pto gear to some success but not a engine crank. i would suggest replacing the crank it would be fairly cheap buy a used crank then get appropriate new mains and new big ends a few gaskets whould be about 100 + used crank which shouldnt be much more than another 100.