XC90 2.5t dead #3 cylinder

Post by **mrbrian200** » 10 Oct 2018, 16:29

Pilgar wrote: 07 Oct 2018, 20:32 ...Seems like some years had this type of check valve and others just had a small hole.

The difference might not necessarily be by year but by engine configuration. I'm pretty sure NAs have the PCV connection there with a ball-less banjo bolt. NAs wouldn't need a check valve as there would never be positive pressure in the manifold.

If I'm wrong about any of that, spell out what engines don't use the check valve in the banjo bolt and/or alert a mod to have this reply deleted.

69ragtop · Post by **69ragtop** » 10 Oct 2018, 22:31

Follow up to original post: After the installation of the 2nd replacement engine (1st one looked suspicious, and turned out to have 3 weak cylinders. Supplier replaced it with a unit that looked well cared for and leak tested very well), the car is back up and running great, but did give me a bit of trouble on initial start up when it wouldn't idle smoothly or rev past 2k RPM, and threw the dreaded throttle body code. Turned out to be a bad connection, and the replacement wiring harness between the ECM and throttle body has been ordered ( around $40). While everything was apart I took advantage of the opportunity to change the motor mounts, drain the torque converter and transmission cooler and refill with the correct Mobile fluid, also changed the angle gear and power steering fluid. I'm pretty happy with the way it turned out but still a little upset that the whole ordeal could have been avoided had I known about the PCV valve. Thanks to all who have contributed to solving the mystery of the dead cylinder, and if you need any 2.5 engine parts, let me know.

Post by **mrbrian200** » 10 Oct 2018, 23:44

Between 69ragtop and Pilgar that's two MY06 2.5T blown engines from this issue popping into the same forum community over a very short time. There might be something to this. Suppliers such as FCP or IPD might consider helping to raise awareness by attaching a warning about this bolt to the product description of all PCV parts available on their sites.
Are there any known TSBs from Volvo regarding this or was the updated part just sort of 'silently introduced'?

Post by **RickHaleParker** » 11 Oct 2018, 03:07

SuperHerman wrote: 18 Sep 2018, 20:54 Curious that the exhaust valves have marks but the intake do not if I am seeing the head right.

1. Intake valves tend to be Martensitic steel to deal with the temperature cycling, cool intake/combustion.
2. Exhaust valves tend to be Austenitic steel to deal with higher temperatures, combustion/exhaust.
3. Austenitic steel is harder then Martensitic steel.

The damage pattern indicates whatever got in the cylinder was harder then the Intake valves and the Head but softer then the Exhaust valves.

69ragtop · Post by **69ragtop** » 11 Oct 2018, 05:22

Yesterday while cleaning the shop curiosity got the better of me and I took the head from the original engine, put a spark plug in #3 cylinder, leveled it with the combustion chambers up and filled #3 with anti freeze level with the head surface and waited. After a short while a small, slow trickle of anti freeze appeared in #3 intake port. I'm not going to pull the valves to determine what one is bent because I'm satisfied the demons have been exercised, but I'm sure this engine can be saved. If I'd have known the first one I was sent would turn out to be a dud I would have gone that route, but overall I'm satisfied, the car's in much better condition now than when I bought it, of I can get another 4 years or so out of it, it will have been worth it, it is a very nice unit.

Pilgar · Post by **Pilgar** » 01 Jan 2019, 19:40

Now I have the photos to show the issues I had. My wife's car was killed by the Banjo Bolt BB and parts. I swapped out the potentially engine killing Bolt from my car and made sure the Bolt was updated in the replacement engine for her car.

: XC90-Banjo-Bolt-Issue.jpg (35.13 KiB) Viewed 1328 times

Post by **cn90** » 01 Jan 2019, 20:18

Hi,

- Could you post the PN for the "Updated Banjo Bolt"?

- Where is this bolt located in the 2.5T engine?

- Can I remove the Banjo Bolt and modify it (i.e. gutting it of the internal parts), then re-install the Banjo Bolt?

I found the post that shows the Banjo Bolt, scroll down to post #33:

https://forums.swedespeed.com/showthrea ... -Questions

Pilgar · Post by **Pilgar** » 02 Jan 2019, 18:22

- Could you post the PN for the "Updated Banjo Bolt"?

- Where is this bolt located in the 2.5T engine?

- Can I remove the Banjo Bolt and modify it (i.e. gutting it of the internal parts), then re-install the Banjo Bolt?

The Banjo Bolt in the Photo is the newer version that so far has no failure history. You can clean it up and reinstall.

Post by **cn90** » 02 Jan 2019, 18:36

This summer, I plan to do the PCV on both:
- 2004 V70 2.5T with 110K.
- 2005 XC90 2.5T with 120K.

I plan to re-use the Banjo Bolts, but...I will first remove it, if there is a pin/BB, then I will remove the guts.
I have read the purpose of the restrictor (pin/BB system) and I am not worried about gutting the Banjo Bolts.

If anyone sees the "con" of gutting the Banjo Bolt, please chime in.