How to compression test a 300tdi

hardness check

have the valve seats cut back 5 thou

have 5 thou taken off the valve by means of the seating cut

make sure the pads are within 5 thou of level

stick the fat gasket in

bolt it together.

do not worry about the compression. I'm quietly certain that the combustion pressure is higher in a tdi thats pushing 25 PSI of boost than the piffiling of rise your going to get out of a 20thou shave. I'm very vocally going to assure you that it is less than one pushing 30psi in.

theres a simple harness test that uses a ball bearing in a tube. its a fixed height you drop the ball and measure the bounce back.

I forget the distances

:):)Thank you Dave. Are you referring to the shaved head or the one I still have bolted to the spare D1 I bought?:D:D

Hi Gerry, Dave's referring to the already shaved head. He reckons my concerns regarding increased compression in no.1 & no.4 being a problem isn't really and I'll defer to his experience here. His argument re pushing 25 psi vs 30 psi or higher is pretty compelling. :)


Apart from that we're pretty much on the same page on the basic technicalities of it all.


Taking 5 thou off all the valves and seats will improve the stand downs by 10 though across the board and with a zero hole gasket will ensure no valve to piston contact. And there's still the pad shimming or machining (whichever way you go) to line up the rocker shaft pedestals. Also the hardness testing which should be done first so that money isn't wasted machining the valves (and pads) in a soft head.


It's a matter of cost really and depends whether you're a 'better the devil you know' or a 'tossing good money after bad' type of person. :D


Deano :)

Quote:

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Originally Posted by wedgetail37

..........................I started on the Timing belt today. I got the Harmonic balancer off (quite a job) and the cover. I can see all the gears and belt. I will paint pen mark the belt and each gear (crank, Diesel pump and camshaft gear). I will transfer the paint marks to the new belt and fit with the marks lined up with the 3 gears.
Do ya reckon that will work??:confused::confused:

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Gerry DO NOT remove the timing belt unless you have pegged the flywheel and the injector pump. :eek: This is very important. The procedure is fairly straight forward and outlined in detail in the maintenance manual I linked to earlier. Follow it as written, no shortcuts. :)


There's a thread currently in the D2 section regarding where this didn't happen :wasntme: and believe me you don't really want to go there.
The only tricky bit is holding the tension on the belt tensioner (11 Nm not the 15Nm stated in the document) when torqueing its retaining bolt up.


Deano :)

Hey Deano, you stopped me before I got to bugger up. I was just looking for the link you sent to the maintenance manual. Cant find it but I will look again.

http://www.aulro.com/afvb/attachment...1&d=1425532840

:):)I hope this works. never done a picture attachment before.

In case it doesnt, here is the problem. Got the timing case off. Got the injector pump gear and flywheel pegged. The belt tensioner on the left with allan key bolt inserted is very tight. Is this a right hand thread or left hand??

Dont want to put too much pressure on it until I know. Thank you - Gerry:D:D

Hi Gerry, here's another one I prepared earlier.


https://www.aulro.com/afvb/images/im...15/03/1341.jpg




BEFORE you remove the old timing belt there's a couple of things to do


1/. Ensure the injector pump is pegged with a suitable pin (arrow 1), can't remember the correct diameter but it needs to be a firm fit.


2/. The two highlighted marks should line up on the cam (arrows 2) drive gear and the lug on the timing cover housing.


3/. The woodruff key (arrow 3) on the crankshaft should line up with the cast mark (arrow 4) in the timing cover. Can't see it in this picture.


4/. Make 'abso-bloody-lutley' sure the flywheel is correctly pegged. It's a very good idea to have the battery disconnected when doing this. I shudder to think of the potential damage if the starter motor was energised with either of the locking pins in. :eek:


The link I'm referring to is back in post 21.



It's a good read.




Deano :)

head back to one of the primers I listed up earlier.

it shows you how to do the timing belt without the tools if you havent snapped the belt

:):)Well guys, my Landie is in many bits at the moment and my limited knowledge of messing with petrol motors over the years has helped me understand the instructions you guys have given me. But without your help I would have been in the **** and my Landrover would be in a diesel repair centre with a huge bill at the end of the day.
I have had a limited budget to get the Beast back on the road. I am not a wealthy man as I am on a disability pension. It is hard work at times for me to do this job but I find it challenging and rewarding as I learn.:eek:
I have been advised to sell my Landie and get a car thats cheaper to run and fix (Some people are totally bloody stupid, Its not an option). I already have a Toyota Corolla that I use for everyday running around and it is great for that purpose and cheap to run and fix, BUT it cannot do what I want to do. I really do love my Landie as it gives me the freedom to enjoy the things I really like doing.
Getting back to you guys, when i joined this Forum/Club it was free but I guess I took advantage and didn't pay my dues as I didn't have to and I was penny pinching.
I am more than happy now I have paid and intend to pay more when I get a few dollars saved after this expense because the help, friendliness and commitment by many members is gold to me. Thank you all so much especially those that went way out of their way to offer assistance . You guys know who you are.

As I said, my Landie is in many pieces at the moment, but I am sure that one day the Beast will be back on the road and taking care of me and my family. After all, it is a Landrover. Warts and all - she is a beauty .... and she is mine. I own a Legend.:cool::cool:

Hi again Gerry, Dave is correct in saying that the job can be done without using the 'pegging' tools, but for you I don't recommend this (which is why I didn't mention it). :)

For someone who is experienced in working on these engines or a professional mechanic, no problems; but for someone such as yourself who is working at the edge of their current knowledge and with no diesel engine experience I don't reckon it's worth the risk. If any of the drive cogs should get out of sync it can be very difficult to get it right again and in my opinion is not worth the risk.

It's pretty easy to avoid this happening by pegging the flywheel through the threaded drain hole and by pegging the injector pump (before the old belt is removed) as shown in my last post.


This is what you need.


https://www.aulro.com/afvb/images/im...15/03/1332.jpg


The injector pump peg (LR special tool LRT-12-045) I've used is a 9mm drill bit with a piece of hose over the sharp end so I don't cut myself and the flywheel peg (LR special tool LRT-12-044) is a ground down 1/2" ? UNF bolt.


I strongly suggest you do it the recommended way (as per the LR maintenance manual in the link I posted), at least for the first time :D as I reckon you'll get more out of it this way :), and there's less chance of 'cocking it up'. :o:)


On the first one I did I also marked the cogs and old belt with a marker pen as an additional backup, as you suggested earlier, paranoid perhaps but better sure than sorry. :D


Deano :)