2006 XC90 2.5T Timing Belt Flew Off

[SoapyCoyote]

Maybe it's cheaper to take to a machine shop and service the current head that's on there now.... will post pics soon.

[SoapyCoyote]

Well if a picture's worth 1000 words.... here's a video https://www.youtube.com/watch?v=Rc6ZeUuhT0U

Also, here are a few concerns I have at the moment:

• Not sure what is causing the spark plugs to have oil in them.

• Don't know why the old Headgasket is 3 layers thick and made out of metal, is this normal?

• Should I clean off the pistons like this? https://www.youtube.com/watch?v=ZlGgkJQJM90&t=763s

I am thinking that I'm going to take this head into a machine shop and have them check all of the valves, check for warping and maybe have them clean it all up plus the valve cover too. Any ideas/suggestions about this? Ballpark estimates of what they will likely charge me for this? Thanks guys! I've never been this far into an engine and I've learned a ton thanks to you guys.

[precopster]

When you seal the head with the anaerobic sealer and small paint roller, you'll also replace 5 o rings and you'll eliminate any leaks that may have caused the spark plug holes to fill. Also oil ON the spark plug electrodes is a sign of either worn valve stem seals (guides will usually outlast the car) or worn piston rings. If car used copious amounts of oil and had high levels of blow-by and PCV pressure you'll want to reconsider a rebuild.

The machine shop can replace the valve stem seals as part of the head service. Take a look at Clearwater heads and see if they can help as all their heads are fully reworked with new valve stem seals for a fixed price.

Most leaks in the spark plug wells are caused by the gasket on the oil filler cap which is a no-brainer bi- annual routine Volvo maintenance item.

Yes head gaskets are composite metal and other materials. Nothing unusual about the head gasket in your video by today's standards. Use gasket stripper and a plastic scraper to remove. Some of the leftover material on the cylinder block will require 5 or 6 passes with gasket stripper and a scraper.

Whatever that guy says about VW blocks also applies to Volvos. Blocks are usually straight especially when no overheating has occurred.

Cleanliness is a must however with the last 2 or 3 I've done I don't make them clean enough to eat from because:
1) I want to have a life
2) The dirt didn't cause the timing system to fail.
3) I can run premium fuel and fuel cleaner to do the same job over a longer period (though I would clean the pistons and bores to a reasonable level)

[oragex]

I'd throw those lifters in something like that to make sure they don't have sludge inside. The piston rings may also be stuck, that may have caused the cylinder wall wear. Try shaking the top of the piston see if it moves easily towards the front/rear of the cylinder. As above, great moment to check the PCV including the oil pan passage.

[SoapyCoyote]

Thanks Precopster! I looked at Clearwater cylinder heads Volvo page here: https://www.cylinder-heads.com/automoti ... ads/volvo/ but they didn't list my engine which is: B5254T2 I could call them and see if they have them or if other heads are compatible with my engine. All of their Volvo heads were listed at $600 anyway, so that did help me get a ballpark figure for how much to expect this job to cost if I were to have it done locally here in Utah.

Oragex that's a great video on how to get stuff cleaned thank you! I don't think I will be following the video I posted previously about using WD-40 and Green Scotch Brite pad to clean anything near the inside of my engine as there is Aluminium Oxide in the green pads which is often used as a diamond substitute in industrial grinding applications so that would most likely not be a good thing for my engine... maybe the blue pads are better? I don't know. I'll check to see if my piston rings are stuck by checking for wobble on the tops of my pistons. I'd like to check my PCV system, but I need to find a good video on how to do that. I don't think I'm going to clean the tops of the pistons at this point because I'm concerned that I will just end up dropping debris down the cylinder walls and make things worse. I have heard that Marvel Mystery Oil can help loosen stuck piston rings, so if they are stuck I'll give that a try.

[SuperHerman]

I paid about $250 for my heads to be cleaned, milled and inspected, which included the upper cover. The shop I used was not my normal shop - which charges $100 for cleaning and milling. I elected to go with ultra-sonic cleaning because the head was really dirty.

I handled the valve lapping and valve stem seal replacement to save costs and maintain quality. I trust my work.

Your engine looks to be in very good condition. I would think the extra oil in some of the cylinder heads is most likely due to worn valve stem seals - but that is just a guess. Oil in the spark plug wells comes usually from two places - oil coming in from filling it/overflow or the black rubber O rings have aged and are stiff. You need to look at the oil pattern stains - it appears the stains are coming from the top to bottom - that points to overflow when filling. The baffle below the oil cap, built into the upper cover, makes for a slower fill and if one rushes it overflows and finds its way into the nearest spark plug wells.

I usually clean the piston tops by scrapping with a plastic pic - the carbon chips off. I do this with the piston at its highest point and I vacuum and clean constantly. Then I lower the piston and clean the walls. Going slowly lowering the piston a bit at a time to pick up everything. I recycle and do it again. I don't always get everything but I do the best I can.

I do not use green, blue, brown or other pads - they leave residue particles that are bad bad bad for engines. I use cleaner and a rougher cloth. Also a razor blade ever so carefully. It is tough going and takes time.

The actual cylinder head is easier as you can clean it - so green, brown, blue pads are an option. Just rinse really well.

After each cylinder is clean wipe area with motor oil to prevent flash rust. Before final clean recylce the pistons and wipe and oil again.

To be clear - the block to head uses a gasket like you show - MLS type - multi layer steel. The head to upper cover uses the sealer mentioned. This is done last.

The PCV system is right there on the pass side of the engine. Removal is super easy where you are at. Take it out - look for sludge and crud and either clean or clean and replace. You have to examine the condition of everything. Me, I would replace everything as it is easier than coming back later.

What does the bottom of the cylinder head look like?

[mrbrian200]

With regard to freeing up potentially stuck piston rings. On some engines the simple switch to a top tier synthetic motor oil will work rings loose and clear the junk over the course of a couple months/few thousand miles. Does that work on these engines?

In your video you expressed concern about protecting the cylinder walls from atmospheric moisture. I don't know how prone (or not) Volvo cylinder walls are to surface rust, but I would probably wipe the cylinder walls with a soft cloth and engine oil. Lay plastic wrap flat across the top of the block, then a folded plush towel on top of the plastic wrap, then few pounds worth of anything you can find laying around to weight over it evenly, or cut a couple 2x4s and lay them across the towel. If it's outside cover the whole thing with a small tarp down the side of the block as much as possible. If it's in a protected/dry garage it will be fine without the tarp. You're looking to have it back together within a couple-few weeks. If it were months or longer and outside you'd need to take further measures. But for a short period this should be more than adequate.

Everybody says the bottom end of these engines is very long lived/solid as a rock. You can still clearly see the honing marks like its barely broken in yet... but at 200,000 miles. I can't quite wrap my head around that. It's a little late now, but had I bought one decent Volvo 20 or 30 years ago I might have avoided a whole string of crappy used Fords/Oldsmobiles/Chryslers and just kept up one decent brick the entire time.

[SoapyCoyote]

Welp just got the head back, that machine shop wants $1000 because they said that the valves alone were going to cost over $300 and that every valve was bent. I'm thinking about going with Clear Water Cylinder Head now for $600.

[SoapyCoyote]

I'm also thinking about just replacing the valves myself. Any good advice on what tool to put the new valves in with? Any good video's out there? My engine is the 2.5 liter turbo engine. I think the engine code is B5254T2 according to Wikipedia. Also, I'm thinking about pulling a head from a salvage yard possibly off of an S60 or a V70 which again according to Wikipedia both can have the engine B5254T2 but it looks like it's not the 2.5 liter but the 2.4 liter? are those still compatible? Maybe it's just a typo.

[precopster]

The B5254T from 2003 and up on turbo V70s and S60s has 2521cc capacity and twin CVVTs same as yours.
If you replace the valves you will need to machine each valve for clearance. Clearancing the valves is tedious and the bucket tappets must be numbered for location.

They usually bend them all.

I use the CTA Tools 2235 Overhead Valve Spring Compressor Kit from Amazon for Volvo white block heads.