timbo's engine woes.

[timbo]

For those that don't know me, for a bit of car spec info:



1995 300tdi 178,000kms on the clock.
Garrett VNT variable vane turbo.
Turner Performance head.
Gas fumigation, pre turbo.
3 inch mandrel bent exhaust.





It started a couple of months ago, with a slow loss of coolant
coolant loss got quicker
As it got colder, I started her up, and it was almost displaying a hydraulic lock. Reluctant to turn over. Starter motor sounded strong, but like it was facing resistance. Also blowing a very light grey, almost white smoke, sweet smelling.
Only started it twice with these conditions. Both times, after the engine was warm, all symptoms disappeared. Decided conrods were fine, but not to take chances.
Got it hauled to the shop, and had the head taken off and tested at the machine shop. Apparently it showed a hole upon testing, but that was already a theory, so maybe confirmation bias skewed the results. (you'll see why I form this opinion in a sec)
Today, a month or so after I get the car back, and it has been sitting in the driveway, a couple of AULRO members came round and we set about changing the head to a new Turner performance head.
Everything goes smoothly, but when we start it up, we get the same smoke.
However, no symptoms of hydraulic lock. Engine turned over a few times smoothly before ignition.
Tried disconnecting turbo, still blowing smoke.
Tried draining coolant (actually just tap water today, but coolant a month ago, though same exhaust smell) and firing her up. Still blew smoke.
Tried cracking open injector pipe connecting nuts slightly up at the head while running, all spraying diesel, though the front was spraying it a little weaker.

Hoping it's not a cracked ring. Gonna check out the timing tomorrow. Hopefully also not a cracked block.

Any thoughts/suggestions/theories?

[Blknight.aus]

is your ga fumigator plumbed into the cooling system? it ight be weeping in.

is the VNT one of the water cooled ones?

have you tried swapping out the diesel? IVe had odd batches before and I get all kinds of wierd exhaust colours and smells depending on what Im doing for WVO.

you could also have dribbly injectors that after shut down dribble as they leack down the holding pressure in the injector lines.

try this....

warm the engine up, then let it idle and stall it out by opening all the injector line unions then killing the ignition. let it sit tillit cools down then tighten up the unions and crank it till it starts.

if you dont get the smoke and smell its the injectors leaking after shutdown.

[timbo]

94842attaching this photo via tapatalk app, hope it works. This is the "old" head which may or may not actually have a problem with it.

Channel your inner sesame street. One of these things is not like the other.

[timbo]

is your ga fumigator plumbed into the cooling system? it ight be weeping in.



is the VNT one of the water cooled ones?



have you tried swapping out the diesel? IVe had odd batches before and I get all kinds of wierd exhaust colours and smells depending on what Im doing for WVO.



you could also have dribbly injectors that after shut down dribble as they leack down the holding pressure in the injector lines.



try this....



warm the engine up, then let it idle and stall it out by opening all the injector line unions then killing the ignition. let it sit tillit cools down then tighten up the unions and crank it till it starts.



if you dont get the smoke and smell its the injectors leaking after shutdown.


Gas is completely off at the tap, and also, testing without turbo meant we had air coming straight through the hose to the plenum, no chance for gas to get involved.

VNT not cooled at all.

My diesel is just servo diesel. It's running on the sub tank at the moment, so I can flick it back to the main tank to give it a shot. Wouldn't explain the loss of water over a the period of a few months though.

Will look into dribbly injector theory, but we'll still check the timing belt today.

[cafe latte]

Timing does not have to be far out to get a lot of smoke. How is it running otherwise is it missing or is it running smoothly?
Chris

[Rick122]

Symptoms sound like LPG is leaking into the coolant or coolant into the gas converter. Try bypassing the converter for a while and see how that goes.

[timbo]

Timing does not have to be far out to get a lot of smoke. How is it running otherwise is it missing or is it running smoothly?

Chris


With the old head on at least, when it warmed up, it ran so smoothly, you wouldn't think there was an issue. No smoke either. That's why we thought there was a hole in the head, closing up with heat expansion.

[timbo]

Bent #4 conrod. Standby.

[cafe latte]

Bent #4 conrod. Standby.

That would do it for sure. Not good though, I hope there is no other damage
Chris

[timbo]

That would do it for sure. Not good though, I hope there is no other damage

Chris


Only enough damage to have to bore it out. Block _should_ be ok.

You guys are gonna hate me for admitting this, but the day was saved by a Land Cruiser driving diesel mechanic. The partner of my parter's friend. He was able to diagnose it within minutes. We swapped two of the injectors, cracked the lines while it was running, and watched for loss of power/no loss of power, and absence of smoke. So he saved us a lot of time.

[timbo]

Also, up until today, we thought there was a chance I had 2 good heads, but the original Turner head must have let water in somehow to initiate the hydraulic lock and bent conrod.

A lesson for everyone here who's as dumb as me: if you're losing coolant, don't assume it's a hose somewhere. It could be the head, and lead to some very pricey knock-on issues.

[timbo]

I'd like to extend my sincere thanks to the forum members who have been helping me the last couple of days. You are saving me a lot of time and money, and I am eternally grateful. You haven't mentioned what your poison is yet, but when I scrape whatever funds I have leftover after this is paid for, I'd like to share a few with you. Also can't wait for the inevitable celebration off-road adventure that we'll have to partake in.

[timbo]

94904ruh roh

[cafe latte]

Only enough damage to have to bore it out. Block _should_ be ok.

You guys are gonna hate me for admitting this, but the day was saved by a Land Cruiser driving diesel mechanic. The partner of my parter's friend. He was able to diagnose it within minutes. We swapped two of the injectors, cracked the lines while it was running, and watched for loss of power/no loss of power, and absence of smoke. So he saved us a lot of time.

Off topic, but I had a similar issue with my 26 tonne cat d7 dozer. It smoked from when I bought it I rebuilt the motor and the darn thing still smoked. I had my oldest in years friend over and we were talking, he is 86 but still fit and active. He asked to come and see my woes with the dozer. He said "lets look at the injector lines and see where they go"..
One went to one and two went to two but four went to three and three went to four. On investigation four injector pipe would not reach tree as it has snapped at some point and been bodged so they has hooked it up as it was wrongly. It smoked so badly, but the moment be cracked the injector no 4 the smoke stopped. When we hooked it up correctly the dozer ran like never before.
Back to your problem a bent conrod you would have had little compression when needed and a lot of smoke.
Is there any other damage, I have my fingers crossed you have been lucky ?
Chris

[PhilipA]

ruh roh
Nah just a couple of whacks with a hammer and a polish and she'll be right. LOL
Reminds me of an acquaintance in the Range Rover club who rolled his 300Tdi . When they righted it he tried to start, with a similar result.
Regards Philip A

[loanrangie]

Timbo, i have some spare rods so you can have one for postage cost.
Piston as well if you can use it but not sure if its std or oversize.

[timbo]

Timbo, i have some spare rods so you can have one for postage cost.
Piston as well if you can use it but not sure if its std or oversize.


Thanks for the offer, but we've already lined up some at this stage. I'll be in touch if that changes. Cheers.

[damienb]

Really quite surprised this wasn't evident with the head off - wouldn't it be a few mm lower than the paired cylinder (or even where it should have been)? I guess easy to say in hindsight.

[timbo]

Really quite surprised this wasn't evident with the head off - wouldn't it be a few mm lower than the paired cylinder (or even where it should have been)? I guess easy to say in hindsight.

When the original mechanic pulled the head off, he didn't do a compression test, nor did check the height of the pistons in relation to each other. That being said, we didn't either, but the pistons weren't aligned in such a way as it would have been obvious when we first looked at it. At that stage we thought it was the cracked head causing the entire issue, not just an initial catalyst.

[Rick122]

First rule I follow any time I take the head of any motor. TDC # 1. You may have seen the height difference on number 4 compared to number 1.
Anyway, hindsight is a wonderful thing.

[cafe latte]

Check the crank for cracks just to be safe. I have known crank shafts crack and stay together.
Cheers
Chris

[timbo]

Check the crank for cracks just to be safe. I have known crank shafts crack and stay together.
Cheers
Chris
Cheers mate, will do! Also means I can stop worrying about having to check my big end bearings.

[timbo]

Well, the beast is back on the road, many thanks to JBoot and all others who helped.

There's a few little things to straighten out, but besides a noisy fanbelt which will be replaced shortly, it's running a lot quieter, and smoother, and pulls a fair bit harder.

Very happy with the results.