Volvo 960, what Have I done!

[CNicholson]

Hello again,

I spent a bit more time on the head this weekend, Unfortunately haven't had a huge amount of time to work on it this week due to work and other stuff.

Removed valves , below is a picture of the worst affected valves. Quite bent! as you can see.


Here is a picture of the worst affected piston crowns, whats the general opinion, is this sort of damage ok to run with? I am very tempted just to file the burrs off and leave them.



Then started cleaning the bits up, first just giving them a quick cleanup with some engine de-greaser, then I will take them to work where they have a parts cleaner. I will take the inlet manifold off and clean that at the same time as its a bit grubby.



Unfortunately one of the valve guides has cracked, this is a real shame because it complicates the job somewhat. I will need to press it out after heating the head up in an oven, then install a new one. I will make sure I take pictures of this.

So now I have inspected the head I need to order a load of parts.

>> Whats the general consensus when buying valves? If you look online you can spend anywhere from £3 for a valve up to £35. What is a respectful brand of aftermarket valves? I want to change all 24 of them so don't really want to spend £30 odd on each one!

>> I am going to buy a gates belt kit with water pump, I have also found a guide to upgrade the cam sprockets, so will incorporate this mod too. Are there any brand recommendations for timing belt kits?

>> Head gasket kit, and stem seals. I am looking at getting a Elring kit, again any recommendations based on experience would be welcome here.

>> Sundry items - the volvo sealant compound for the valve cover, acetone, oil, coolant, filters, general service items, spark plugs etc may as well do a bit of a service whilst I am poking about, is there anything else I should do whilst I am at it?...

>> I broke the timing cover by accident! will need to replace this, probably off a scrapped vehicle.

I will update this thread as I go so as to help others in a similar position, my plan is to do it without using any special tools, only stuff the average DIY mechanic might have to hand. Only job where I might need some industrial help is the cracked valve guide, but I am sure I will think of a way of doing this job.

[atco]

great work mate .eny chance of some photos of the cracked valve guide.if poss thanks

[CNicholson]

Yes once the castings are fully clean I will take more photos.

I have been looking into changing the valve guide, some suggest forcing them out with a power hammer, however I am worried this may damage the bore, and I don't really want to be faffing about with reamers for oversized guides. I think the best way to avoid damage is with a hydraulic press and some drifts.

[Laird Scooby]

Originally Posted by CNicholson

Yes once the castings are fully clean I will take more photos.

I have been looking into changing the valve guide, some suggest forcing them out with a power hammer, however I am worried this may damage the bore, and I don't really want to be faffing about with reamers for oversized guides. I think the best way to avoid damage is with a hydraulic press and some drifts.

I would strongly suggest you find a local engineering machine shop and entrust the replacement of the valve guide to them. While the head is there, have it crack-tested and also tested for flatness - the last thing you want is to rebuild the head and make an amazing job of it then find that when it's back on the car that it either has cracks you can't see, is no longer flat or worse still, find you have caused some damage by removing the valve guide in a less than ideal way.
It's also entirely possible that there is other damage to it already, so far unseen that won't show up to the naked eye but will show up during crack testing and/or machining.

The cost involved would be a small insurance premium to pay against the possible further costs if any of the scenarios i've suggested are present. It also means if the machine shop damage the head head during removal and/or refitting of the valve guide that it's their fault so they would then have to bear the cost.

I appreciate you may well be on a budget doing this job and while this expense may seem pointless, out of your budget or whatever else, it will still be cheaper than having to buy a second head gasket set and a secondhand head. It will also give you peace of mind that there are no other problems at the time.

As for the damage to the piston crowns, i would suggest cleaning the burrs off with a small file followed by emery cloth then polishing the top of the piston with Solvol-Autosol to as near mirror finish as you can get.

[classicswede]

Timing belts I only ever fit genuine Volvo belts. Price is often less than aftermarket.

Head sets I stock both 2.5 and 3ltr gasket kits


The pistons look fine, just give them a quick clean up

As above I would take teh head to a engine builder to get the valve guide done. It should not be expensive

[Piet22]

Very nice writeup!
Re loosening the nut that holds the inlet manifold: using a short (ca 5 cm long) ring ratchet with 72 teeth (allowing small strokes) makes it a lot easier. No need to climb on top of the engine, it can be done just standing alongside the car.

A nice picture of the situation is on turbobricks: http://forums.turbobricks.com/showthread.php?t=87806

Piet

[CNicholson]

Good evening.

Thanks Classicsweed and Laird,

I acknowledge the need to test the head to make sure it is in good shape, and I also understand a engine shop will be better equipped to sort out valve guide problems. I plan to do further inspection to the head myself, and will then make a choice as to what to do afterwards.

I prefer to do as much work of this nature as I can myself generally, I enjoy the challenge and if I do end up scrapping the head at least I will have learnt something in the process.

I am going to post photos to fill in the blanks:

I took some photos of my valve removal tool, I used a standard valve compressor, but had to make an extension out of some 25mm steel tube. I used a socket in the end to stop the valve compressor from slipping off, and I wrapped both ends in tape to prevent the steel from marking anything.







Head with no valves



Poor bent valves



even the valves that look ok are still either bent or the seat face was warped.

After giving the castings a rough clean with some engine degreaser I took them on a trip to work where there is a parts washer. Unfortunately the head was too big to fit in the rotary parts washer, so I did it in the manual parts washer.

I used acetone, a brass brush, some scapel blades, and a load of elbow grease to get the thing cleaned roughly. There is still some of the anaerobic sealer on there, but I will remove this later. I took a picture of the cracked valve guide.













There is still a bit of cleanup to do, however I am quite satisfied that the block is flat. Now just need to decide what to do about that pesky valve guide!

General state of play:



Good Night.

[rwdkev]

Originally Posted by classicswede

Timing belts I only ever fit genuine Volvo belts. Price is often less than aftermarket.

I'd be the first to say that blue box prices are often daylight robbery but Dai's right, as has been mentioned on this forum before - Volvo cam belts are surprisingly cheap for some reason. I did my V90 only a few weeks ago. I'm keeping the car for the foreseeable so wanted piece of mind. Having said that, the one that came off was a Gates and it literally looked brand new despite being due for replacement!!

[Laird Scooby]

Originally Posted by rwdkev

I'd be the first to say that blue box prices are often daylight robbery but Dai's right, as has been mentioned on this forum before - Volvo cam belts are surprisingly cheap for some reason. I did my V90 only a few weeks ago. I'm keeping the car for the foreseeable so wanted piece of mind. Having said that, the one that came off was a Gates and it literally looked brand new despite being due for replacement!!

Gates are good belts and i think they actually supply Volvo. Just glad i don't have to worry about mine!

[360beast]

Originally Posted by Laird Scooby

Gates are good belts and i think they actually supply Volvo. Just glad i don't have to worry about mine!

I used gates on my 940, it had the correct timing marks on the belt where as the genuine Volvo one on the car didn't.