2000 V70R B5244T2 cylinder head rebuild

choogenboom · Post by **choogenboom** » 16 Jan 2012, 19:05

Hi All,
The timing belt tensioner in my V70R seized up, the timing belt was therefore shredded and all the valves bent. I am in the process of pulling the head for a rebuild by Clearwater Cylinder heads. Any tips or advice you all can share would be very much appreciated. I'll try to post what I have learned here as well as some photos.

I pulled the head yesterday; it took about 5 hours start to finish including a trip to hardware store for 14mm 1/2" socket + extension, as well as 1/4" swivel. Some comments and questions:

1. Whoever designed the cooling water pipe to head connection on the back (exhaust) side of the head was a sadist. Nearly impossible to get to the bottom 10mm bolt. Probably the single hardest bolt to remove on the engine, at least for this repair. Is there some trick to getting at this bolt?
2. All of the exhaust studs came out (ie nuts took the studs with them on the way out), and each had a little aluminum (least I think its aluminum) on them and one had the threads filled with aluminum. This made head removal a lot easier as I did not have to move the exhaust manifold back to clear the studs if they had stayed in. But concerned about the integrity of the threads in the head. Is this normal?
3. Had to cut the hose from the thermostat housing to the intake manifold that appeared to be cooling the PCV gasses returning to the intake. It uses crimp type hose clamps and there seemed to be no possible way to access the clamps and pry them open. Any trick I missed here?
4. The fuel feed to the fuel injector rail has a disconnect coupling on it. I was stumped as to how to gracefully release it (most quick disconnects have an obvious release button) and finally gave a good hard yank and it pulled out. Is this really the right way to release it? (I have the answer to this question. IPD sells a special tool to release this connector. Now what I REALLY don't understand is the other end of this fuel line has a similar connector but it DOES have a release mechanism built in. WHY would volvo design it like this?!)
5. One bearing surface on the intake cam had carbon build up on it, telling me it was not bearing a load. It was the bearing on the far end opposite the timing belt. Is this normal?
6. All the cam lobes had carbon build up on the low side, telling me they were not in continuous contact with the lifters. I understood them to be self adjusting hydraulic lifters. What am I missing? Shouldn’t they “self adjust” to be in constant contact with the cam lobes?
7. The carbon/sludge build up on the top of the cylinder head was progressively greater from left (cylinder 1? Nearest timing belt) to right (cylinder 5?). This seems odd. Is this normal, and if not any reason for this?

Other than replacing the head and all gaskets, what other items should be replaced preventatively? PCV system, turbo oil tube gasket? Anything else?

Thanks in advance for your comments and help.

gilhuly · Post by **gilhuly** » 16 Jan 2012, 19:48

Sounds like poor oil pressure. Likely bad o-rings, but could be an oil pump problem. Did you have ticking lifters? Make sure you get all those oil journals clean and don't plug any of them up putting the valve cover back on. You are going to need to assure you have good oil pressure.

choogenboom · Post by **choogenboom** » 17 Jan 2012, 05:10

gilhuly wrote:Sounds like poor oil pressure. Likely bad o-rings, but could be an oil pump problem. Did you have ticking lifters? Make sure you get all those oil journals clean and don't plug any of them up putting the valve cover back on. You are going to need to assure you have good oil pressure.

No ticking lifters, even on a cold start. I assume this is in response to my question "Why do the cam lobes have sludge build up on low side and do not appear to be in constant contact with the lifters"?

Is there a spoot where a oil pressure guage can be be connected to the block? Remove the oil pressure sensor and connect a true pressure uage? Or?

Post by **jimmy57** » 17 Jan 2012, 08:30

2000 has solid tappets. You will need to have the clearance checked and tappets changed to adjust clearance. The new valves and any seat grinding is going to change things. That is if you kept the tappets in order to begin with.
The lower cam journals are almost never in contact with cam except for the front where the belt pulls down. This is true for every OHC design with direct bucket tappets. The cam is pushing up so the gap there is a couple of thousandths which is plenty for oil film to develop. Several cylinder heads (like the new 6 cylinder Volvo engines) have incomplete lower journals in several locations. The cylinder head bolt access holes take away most of the lower journal .

choogenboom · Post by **choogenboom** » 17 Jan 2012, 15:30

jimmy57 wrote:2000 has solid tappets. You will need to have the clearance checked and tappets changed to adjust clearance. The new valves and any seat grinding is going to change things. That is if you kept the tappets in order to begin with.
The lower cam journals are almost never in contact with cam except for the front where the belt pulls down. This is true for every OHC design with direct bucket tappets. The cam is pushing up so the gap there is a couple of thousandths which is plenty for oil film to develop. Several cylinder heads (like the new 6 cylinder Volvo engines) have incomplete lower journals in several locations. The cylinder head bolt access holes take away most of the lower journal .

Thanks, makes perfect sense. What is the process for setting the clearance and do I need a shim kit?

Post by **sanfelice** » 25 Jun 2012, 15:03

Did you ever get this all buttoned up? What was your experience?