V9X Engine Failure??

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I think Loctite 680 and put the new bearings in the worn block.

Loctite 680 is incredible strong and can fill gaps to 0.4mm.
 
Does anyone have the main and conrod bearing clearance specifications as they are not in the manual I've got; all help is appreciated
 
I think Loctite 680 and put the new bearings in the worn block.

Loctite 680 is incredible strong and can fill gaps to 0.4mm.
I have had the block bored oversize and the crank upsized with "cold chrome" and am using toyota bearings with tabs worked it through with ACL Bearings in Tasmania
 
Does anyone have the main and conrod bearing clearance specifications as they are not in the manual I've got; all help is appreciated

I've looked in the service manual and it specifically mentions this with a "Look in the SDS" for the clearances - and the SDS does NOT have these figures for the V9X. It has them for the YD25 but that's useless to you (I mean, what are the chances that they're the same between an inline-4 and a V6?).

I wonder if there's a newer version of the service manual around, that has this information in it?
 
Just wondering what condition your timing chain is in. I'm wondering if I should replace the chains and tensioners. My V9X has now done 245,000 km. I blocked the EGR with a blanking plate at 10,000 km after the 1st service and blowby is very very little. Better than new. I think the gritty soot wears the rings out and adds to blowby and oil contamination which then allows highly soot contaminated oil to wear the main bearings. I'm glad I blocked my EGR off as I can hold my hand over the engine oil cap and there is not much coming out.
 
Just wondering what condition your timing chain is in. I'm wondering if I should replace the chains and tensioners. My V9X has now done 245,000 km. I blocked the EGR with a blanking plate at 10,000 km after the 1st service and blowby is very very little. Better than new. I think the gritty soot wears the rings out and adds to blowby and oil contamination which then allows highly soot contaminated oil to wear the main bearings. I'm glad I blocked my EGR off as I can hold my hand over the engine oil cap and there is not much coming out.

The answer to your question may not help ... allow me to explain.

My own car has just had its head replaced. Now I haven't had a good look at the old head yet, but it's entirely possible that my head was NOT cracked, and that it was just a head gasket ... but I digress.

During the course of disassembly and inspection (we insisted that they provide and fit a brand new water pump and thermostat) they checked over everything, timing chains included. And I get a phone call.

"Hey it's the mechanic."
"Yep? Problem?"
"Yeah, how long ago did you get this engine rebuilt? I'm guessing 20,000km or so?"
"Never."
"You're kidding me? The timing chains look brand new, as do the guides, and your speedo reads 361,000km"
"You're the first to see that timing chain since the engine was assembled in Spain."

It's another reason why I couldn't understand how we cracked a head. I don't drive it hard, I don't let it overheat ... and she's regularly (and properly) serviced. Even the old water pump (the original one from factory) looks new inside.

So it's going to vary - the condition of components and their expected longevity vary greatly depending on manufacturing quality, servicing (both frequency and quality) and driving style.
 
I blocked the EGR with a blanking plate at 10,000 km after the 1st service and blowby is very very little. Better than new.
Interesting. There maybe something in this. I blocked mine from virtually new. Just after the 1000K check. I was worried it maybe discovered under warranty. Wasn't. Now 10 years latter I have bugger all blow by. To the point I was a little worried as the catch can seems to catch bugger all oil. So disconnected the hose to the catch can and let hang down and swing in the breeze for a while (on closed roads on private property of course ;-) very little oily residue in the hose.

As Tony mentioned I believe a lot rests on how you drive them. Duty cycle- i.e. Cold Starts to the amount of K's counts for a bit to.
 
e SDS does NOT
The answer to your question may not help ... allow me to explain.

My own car has just had its head replaced. Now I haven't had a good look at the old head yet, but it's entirely possible that my head was NOT cracked, and that it was just a head gasket ... but I digress.

During the course of disassembly and inspection (we insisted that they provide and fit a brand new water pump and thermostat) they checked over everything, timing chains included. And I get a phone call.

"Hey it's the mechanic."
"Yep? Problem?"
"Yeah, how long ago did you get this engine rebuilt? I'm guessing 20,000km or so?"
"Never."
"You're kidding me? The timing chains look brand new, as do the guides, and your speedo reads 361,000km"
"You're the first to see that timing chain since the engine was assembled in Spain."

It's another reason why I couldn't understand how we cracked a head. I don't drive it hard, I don't let it overheat ... and she's regularly (and properly) serviced. Even the old water pump (the original one from factory) looks new inside.

So it's going to vary - the condition of components and their expected longevity vary greatly depending on manufacturing quality, servicing (both frequency and quality) and driving style.


Tony. Do you have your EGR blocked off? To check timing chain wear you need to see how far the tensioners are extended and how much travel is remaining.

Also there are two good video's on Youtube about the tV9X iming chaiins.
That russian channel has heaps of V9X videos. Just need captions turned on and translate to english.

See entire vide with auto translate to english set

See 9:06 time


_
 
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Tony. Do you have your EGR blocked off? To check timing chain wear you need to see how far the tensioners are extended and how much travel is remaining.

Also there are two good video's on Youtube about the tV9X iming chaiins.
That russian channel has heaps of V9X videos. Just need captions turned on and translate to english.

See entire vide with auto translate to english set

See 9:06 time


_


My EGR was blocked off but I don't know right now, I haven't had a chance to go over that yet. I let the mechanic go over the chains and tensioners and guides, he called me and asked me how long ago I'd had a timing chain kit put in because they were nearly new. He was stunnned to discover that he was the first to lay eyes on those chains since the engine was assembled!
 
Here's a really tricky question - Has anyone replaced the V6 A9X engine with another V8 or V6 that you can actually get parts for. I am currently advised that regrinding some diesel crankshafts carries a lot of risk (breakage) most engine reconditioners are now refusing to do it (advice from insurers) My vehicle is in exceptional condition and I've owned it from new 220,000 km. and really don't want to replace it. Second hand engines seem to be very scarce and when they are available $15,000 AU$ plus
 
Mine is about to tick over to 250,00 kms.

Have your main bearings spun and damaged your crank? Oversize 0.25mm and 0.5mm bearings are available. You can also hardchrome the crankshaft journals back to original size. I'm not sure about fatigue strength loss however with the plating option.

Other than doing that, I wouldn't be that keen to swap the engine to a V8 as the transmission would need to be swapped out as well.
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Thanks for your info, the bearings actually spun in the block and it required a line bore, which required larger bearings (now toyota !!!) hard chroming the main crank journals to match - now waiting on machine shop to complete the job- one hell of a process but hoping to eventually get the vehicle back on the road
 
Hello Adhau, how you going with it ?
you mentioned you had an upgrade chip, I wonder if that might be making trouble for you ? I met another 550 owner telling me how good the upgrade chip is ... when I asked for a look under the hood I seen the top cover missing, he said I took it off to stop over heating when towing...85k is low km for trouble to start.
wishing you luck :)
 
Hi Cowboy,
I have had no overheating issues, however I would have to state, that I think the chip increases the power to a tipping point of reliability. I have come to the conclusion that the main bearings are simply too small for the load placed on them, when you then add the carbon suspended within the oil (due to the ERG valve recirculating burnt oil) and miss a few oil changes, there is a compounding effect of abrasion and overload - result - bearing failure.
Ironically I love the engine and would consider stripping ALL the EGR related components out (which is most of the "Stuff" in the valley) if there were new cranks and engine blocks readily available. Sadly I have been unable to source either, and am in the process of completing the rebuild which required some innovative solutions and move the vehicle on.
 
5F664E63-F2AB-40CC-B4B3-598BB39EEE22.png
162,000km
 
I see on eBay quite a few engines ... not advertised for sale but they are in the photos. Also one looks hit in the front auto is good and block may have escaped damage. worth a call maybe ?
if you could replace the engine and keep your 550 that would be a great result rather than moving it on and you would have lots of spare parts. I would consider removing the chip... the fact that is a v6 3Lt putting out 170kw 550nm is very incredible in the first place.
hope it helps.. good luck Adhaul.
 
Okay rebuild complete now it won’t fire, thinking I have the timing out, Question is apart from the sensor on the crankshaft what other signal indicates the compression stroke?
 
As far as I know, it's just the crankshaft sensor for that. There are camshaft sensors as well but they're not used for injection timing (that I can see in the manual). The manual indicates that the camshaft sensors might cause the engine to run roughly, but that implies that the engine can still start. A start failure is indicated for a poor crankshaft sensor (among other things, like fuel pump signals and glow plugs).
 
As far as I know, it's just the crankshaft sensor for that. There are camshaft sensors as well but they're not used for injection timing (that I can see in the manual). The manual indicates that the camshaft sensors might cause the engine to run roughly, but that implies that the engine can still start. A start failure is indicated for a poor crankshaft sensor (among other things, like fuel pump signals and glow plugs).
Thanks but there must be a sensor somewhere or something that indicates which stroke the engine is on otherwise it would have the injectors firing on the exhaust stroke as well- yet to plug in a OB2 tester
 
Okay,
Brains Trust all attention is required - I have now rebuilt the engine, all care has been paid to crankshaft and camshaft timing, we have compression, not that it's been measured, but when it cranks over by starter it's pretty obvious. I've; checked for computer error codes - nil, bled the fuel system, still seem to have some bubbles but generally flowing clear, Engine cranks, but nothing indicates any attempt to fire. I'm convinced it's a fuel issue but bleeding is only by the supplied pump unless someone has another answer, or it maybe a timing issue as I don't know how the computer knows which cycle the compression stroke is on. Urgently looking to get this beast back on the road.
 

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