1995 850 2.3L turbo head removal question

gmanter · Post by **gmanter** » 30 Jan 2010, 17:53

Looking for bit of insight. About to pull head, Cam assy's are out and tomorrow will pull head. Do I need to disconnect exhaust manifold from head or can I disconnect exhaust manifold from turbo and let exhaust manifold come out with head and then address the exhaust manifold nuts up on a bench.
Tks Gary

Post by **Ozark Lee** » 30 Jan 2010, 23:01

You do need to remove the exhaust manifold. The upper studs are on the head and the lower studs are on the block.

...Lee

gmanter · Post by **gmanter** » 31 Jan 2010, 18:39

Appreciate help.
Did get head off, unfortunately broke one headbolt off in block. Have filled hole with penetrant and am gearing up to attempt removal with drill guides/ easy out, mid week. Was going to work way up to 23/64 drill , and give ez out a try.
If you have any suggestions would certainly like to hear.
With regards to head I expected to find warp issue but did not , longitudinal and transverse out of flat was less than .003". Now I am left with question as to where I was introducing oil into water system. I have done leak down tests on both oil coolers and now have pulled head expecting to find clear indication of leak path, alas if it is there it does not seem obvious. Will do leak down test on turbo water jacket tomorrow. Any other suggestions would be helpful.
With regards to cleaning head surface a friend suggested that I have it "glass beaded" any opinions on this approach? I was going to simply use some gasket removal goop from Pep Boys.

Thanks Gary

Post by **JDS60R** » 31 Jan 2010, 19:31

If you are talking about the head surface that will touch the head gasket then you must not glass bead it. The head mating surface has a particularly smooth surface on it. The "Ra" of the surface must be within factory spec or the head gasket will not perform correctly for you.

You can use gasket removal compound but be careful not to scrape with anything that would gouge the head.

I have the local machine shop machine it flat and I usually have them service any valve that did not test well after I took it off. My local shop is affordable and the head looks and performs great when you get it back.

gmanter · Post by **gmanter** » 07 Mar 2010, 09:26

Many Thanks to all for help on Head Gasket Replacement 850 Turbo.
My son has put in about 200 miles and knock on wood, oil and water appear to be staying where they belong.
Several insights wanted to pass along from our experience-
A) Sure wish we had been more disciplined regarding writing down sequence of dissassembly and taking some photo's to help with reassembly. We did do a fairly good job of keeping specific small fasteners/components in marked zip lock bags
B) The online service repair manual you-all directed us to was a huge help
C) We managed to break the last headbolt we were removing. We were following pattern in manual, and turning each one 1/2 turn once it broke loose. If we had it to do over again I think I would follow reccommended pattern yet only turn each bolt enough to break it loose, then once all are to this point go through again and turn each 1/2 turn. I was suspicious that it was last bolt which broke and wonder if the load left on that last bolt may have included some of the shared headbolt load. If anyone has an opinion on this we would be interested.
D) Our appraoch to broken headbolt seemed to get the job done, so here it is for others whom perhaps may be like us new to the process- We covered the broken stud with mystery oil and left over night, also while submerged in oil we used a drift to tap/vibrate stud in hopes of getting penetrant down into threads.
We machined up two 2" long drill guides, .580" OD with the ID set for 1/4" and 11/32" drill bits. The guides were to ensure that our hole into broken stud was centered. Using 1/4" guide we went through broken stud with 1/4" pilot hole. We then used 11/32" guide along with left hand drill bit ( friend of ours steered us to this trick). Broken stud began to spin out once bit was half way through. The 11/32" diameter was also correct for I think it was # 5 EZ Out in case left hand drill did not get job done.
Anyway although challenging at times it was great experience to share with my son and thanks again to all who passed along their experience as we went through process

Gary

Post by **Ozark Lee** » 07 Mar 2010, 11:14

It sounds like we have another satisfied customer.

I can really appreciate your son's involvement and it will either be a huge help to him or it will be a curse. I had both my son and my daughter work on cars with me (particularly their cars) just so that they could learn and never be either fooled by a repair shop or dependent on a repair shop.

It has been very rewarding personally since they both really do get it. The down side is that my son calls me from college every weekend with a question about some car I have never opened the hood on since he is now the resident mechanic at his fraternity house. That is the curse part.

My daughter understands grubby clothes and working on cars. Here we are working on her Porsche.

: DSC02136.JPG (208.7 KiB) Viewed 1132 times

...Lee

Moocoo · Post by **Moocoo** » 09 Mar 2010, 06:14

Hey folks,
Can you tell me where to find the online service manual you referred to? I am looking for the vacuum hose diagram for my 97 850 GLT wagon I recently replaced the head gasket on. I used the Haynes manual but it is not detailed enough to supply a diagram. I did post this question last week but have not gotten any reply. Thanks

Post by **Ozark Lee** » 09 Mar 2010, 19:34

Here is an 850 manual that is available on the site.

https://www.matthewsvolvosite.com/downlo ... vo_850.zip

In many ways it is superior to Haynes but it referes to factory tools and has few detailed pictures. Another good source is VADIS which you can pick up on eBay for around $20.00.

...Lee