Engine: T5/R Broke my T5 engine. Whoops.

[Juular]

I had been having some rather strange issues with my C70 T5. It started as being quite sluggish, then developed into a wild surge followed by extreme hesitation especially at wide open throttle.

I did an overhaul of the vacuum and ignition system with all new pipes, clamps, leads and distributor. This didn't really help but while doing that, I noticed that the turbo control solenoid wasn't clicking at all when I gave it 12v.

I replaced it with a known good one and fitted a boost gauge. It sorted the problem and it was reading a consistent 10psi max which sounds about right.

Until I floored it away from a roundabout and then heard the mother of all death rattles. This was literally the most toe curling sound I've heard from an engine.

Yeah, that ain't straight anymore!



That was #1 Conrod which as you can see has suffered the effects of detonation pretty badly.

I am not sure what happened, but I am guessing that the stuck turbo solenoid was failing to open the wastegate and so the boost pressure has been skyrocketing, causing fuel cutoff to occur.

I don't know why the symptoms started after the working solenoid was installed, but there you go.

I pulled the head and pistons.



Banana!



And here is what caused the bottom end noise.

The little end here :



Was hitting the counterweight here:



Thankfully that was the only damage. The car wasn't smoking or using oil so I decided to rebuild. Bear in mind I have never even seen inside an engine before, but at this point there is really nothing to lose!

The big ends were ok but a little scored, so I replaced them.





I bought a set of Maxpeedingrods Conrods. I haven't actually heard anything bad about these so seemed excellent value.



Block and head cleaned up.







Rebuild process.







I couldn't get a hold of the correct anaerobic sealant for the cam cover and oil pan. I took a gamble and used flange sealant loctite 5922 which is much cheaper and easier to get.





It's an engine.



So despite the much sucking of teeth and negativity I received (not on here!).. it runs again and runs well and I'm quite happy.



I did not change the main bearings or piston rings nor did I service the valves. I did change the oil pan O-rings. I used clean engine oil an every surface for assembly but no assembly lube. Total rebuild cost including some new tools and fluids was about £350.

It took me and a friend a day to dismantle and bag the engine. I spent an hour here and there cleaning up the engine parts while waiting on new bits. It took me a day by myself to reassemble and start the engine.

This is quite an easy engine to work on. Worst part of the job is the oil pan. If you are doing this, do yourself a favour and bend the subframe tab out of the way, take the dogbone mount off, and Jack the engine up onto the next bolt hole on the mount under the crankshaft.

Moral of the story, be very careful if you start having turbo pressure problems and fit a boost gauge if unsure! The stock Conrods evidently do not like detonation very much!

[Bonefishblues]

Top work. I was feeling quite smug because I just fixed our bean-to-cup coffee machine, and this has put it in its correct context!

[Juular]

Haha, not at all though, I was hoping this would inspire anyone hesitant to get stuck in as frankly I didn't have a clue where to start. There's nothing particularly frightening about this flavour of T5.

[Shinsplintz 101]

Good effort fella. Fortune favours the brave!!

So many of these cars have gone to the knackers yard due to a bent rod. Well done for getting stuck in an getting it back on the road. Car saved.

Boost low down in the RPMs will bend them chocolate rods in the T5 lumps no problem at all.

Sad you've experience the shiny spanner brigade picking the bones out of it...."why didn't you do X,Y,Z...you should have used A, B, Cà...blah, blah, blah"......but worry not, most of them no bugger all about bugger all, but they do like to sound like they know everythingabouteverything.....but rarely show examplesof their ownwork for others to take a pop at.

Chapeau. Happy motoring!

[BorderVolvo]

Nice wee write-up..... budget bottom end build!!

[Martin Cox]

Well done!

It's very satisfying fixing something like that yourself isn't it. You may not have been inside an engine before but you obviously had a good understanding of how to go about it. The pictures suggest you've taken care to keep everything clean and been methodical; both push the likelihood of success firmly in your favour. Good tools help; knowing how to use them, more so.

Lastly, thank you for sharing it with us. A good write-up is always welcome.

Martin

1998 V70 Tdi Auto 228,000 miles
2008 V70 2.4D auto 122,000 miles

[sdg1970]

Amazing work. Kudos! I wouldn't have attempted that these days and not on these beasts. Basic servicing and probably brakes are my limit now. I would've either scrapped car or paid someone to do it depending on mood/finances..

[Mkengineering]

Fair play to you chap for getting stuck in.

To me seems like you did a top job.

[RollingThunder]

Great job, well done. I didn't think you could take the sump off without pulling the engine as access is so tight - I'm sure a few choice words were uttered when you did this

Thanks for sharing

[Juular]

Originally Posted by RollingThunder

Great job, well done. I didn't think you could take the sump off without pulling the engine as access is so tight - I'm sure a few choice words were uttered when you did this

Believe me, some new 'engineering terms' were invented while doing that particular bit. It's the only part of the job that really caused a headache.

Access is tight but it's definitely doable and still easier than dropping the subframe. You can jack the engine up on the driveshaft retaining collar and hang it off the upper engine mount bolt for extra access. Once you've done it you can repeat it fairly easily, which is good as mine seems to be leaking a bit..