I recently purchased a 1995 850 Turbo with 102K original miles (I checked with the OBD-1 led / button method, to make sure, since odometer gear was "fixed" by PO). It's a beautiful car by the way, black on black with excellent interior and it's so much more fun to drive than my old car, a N/A wagon. I now understand why the 850 turbo's have such a following

Timing belt was last done at 57K. So I'm thinking it's due soon.

In planning for this repair, I read numerous DIY's and threads and still have a few questions.

1) Water Pump. It seems that some people say change it every other belt change (i.e. for me the upcoming one), others say they rarely leak and only replace when it is leaking. So my question are a) is it easy to spot if it's leaking? The whole timing belt area is pretty oily/messy (see #2 below) so am not sure if I should perhaps first clean it and then test it somehow? I haven't really seen pictures of how a leaky water pump looks like. Or would I see water puddles on the ground? b) I'm a bit afraid to mess things up (don't change a running system), to be honest even the TB job I'm a bit worried about itself, so I'm leaning towards not doing the water pump if I can. It would save me some troubles and then once I've gained some experience (and confidence) I can do it in 70K miles (which will be in ~3 years for me).

2) I want to do the Cam seals at the same time. PO reported that when he got the car a couple of years ago the PCV system was clogged, so he installed the kit. I figured the Cam seals probably got a beating with the clogged system, and the TB area in general looks pretty oily/messy so want to do this now - it doesn't sound like a difficult / time consuming thing.

3) I am going to pass on the front crank seal. Or do you guys think I should do it since I'm doing the other seals? Maybe I should post some pictures to have you chime in?

4) I want to switch to synthetic oil (mobil 1 - main reason being that I want to make sure the car will last me some time after I've done the cam seals (I will also do the rear cam seals) and the turbo return line gasket (it's also leaking). I've read that switching to synthetic oil can make seals weaker, hence waiting until after. Any words of wisdom here - anything to check before I use synthetic? Like mentioned breather system is clean (now!). I figured once I've changed most of the seals, maybe the risk of switching to synthetic is not that big anymore. My question is also around the internal of the engine. Can switching to synthetic make piston rings etc become leaky too (I've had an issue with piston rings on my old car that I just replaced with this 850 so hence the question).

Thanks a lot.

 

Here is a link to my timing belt lecture:

How long has it been since the belt was last changed? If not longer than 7 years ago, I'd ride it out till 130,000.

1. I only replace leaking water pumps. They usually leak coolant on the ground while sitting. You can also pull the cover and see a little coolant in the belt cover area near the pump. In the pic below you can see the cooant just under the bolt.



You may also need to replace the tensioner, idler roller and tensioner roller.

2. I usually do not replace the seals unless they are leaking. Sounds like you have a leak or the belt area was never cleaned from the last oil leak. My guess is that they seals are leaking now. You should double check the PCV system with the dip stick trick. The systems only last about 5 years or 60,000 miles from what I read in the manual. Here are my seal DIY write ups. Be extra careful with this job, another user just missed his alignment a little when going back together and destroyed his head when he tried to start the car. Was maybe a couple of teeth off on the cam sprocket install and destroyed his exhaust valves. Sad day doing a head from a alignment mistake.
Cam Seals, Front Replacement, 1998 Volvo S70 GLT - Volvo 850 Cam Seal Replacement
Cam Seal Replacement, rear, 1998 Volvo S70 GLT - Volvo 850 Cam Seal Replacement

3. Again, I only replace leaking seals. But if your PCV is plugs, it may not be long.

4. I always switch my cars to synthetic oil. I think it was the difference of my daughter making it home from a 550 mile road trip when her S70 blew a hose and ran out of coolant. It may cause weak seals to leak but in my opinion, it was just a matter of time on that. I switched my now dd wagon at 190,000 miles. The car's motor is incredibly tight, compression over 175 across the board.

I do NOT believe you need to change so the motor will last. It will run find for years with normal oil as long as you change it often.

 

Thanks rspi. Timing belt was last done in 2006. Reason why I want to do the timing belt now rather than technically perhaps a year from now is that I currently still have my old v70 wagon (remember the one with the worn piston rings) and it still drives but I'll have to retire it in October when SMOG check is up. So I could work on the car and still get to and from work with the second car.

Thanks so much for the feedback. I'll check if the water pump is leaking, the picture will help. I was planning on changing all the tensioners and pulleys (FCP groton "minor" kit).

In terms of the cam seals, I did come across your tutorials and have already printed them Can you tell me where you got them for $9 a piece plus shipping? FCP sells them for $20 each so am trying to get them cheaper

In terms of synthetic oil, I like the idea of having to do an oil change only every 5,000 miles with synthetic as opposed to 3,000 with regular. Is there anything else to worry about when switching to synthetic?

 

Well, the normal oil change schedule is 5,000. So either way 5,000 is the number.

No other things to be concerned about to me.

 

If your crank seal is leaking, you definitely want to change it. What I would do is thoroughly clean the area around there, then check it in a week or so and see if there's any oil coming out of there. FWIW, the crankshaft seal is not very difficult to replace.

RSPI and I kinda do things differently: When I did my timing belt, I did the water pump, cam seals, tensioner/pulleys, and crank seal. Im a "while im right there" kinda guy and he is not. There's valid arguments for both sides of that coin.

 

I also tend to replace anything I can but I plan to keep it a while and I'm also doing performance modifications so I feel the need to make sure as much of it is 100% as I can.
It also depends on difficulty and cost. For all the trouble it is to do a CV axle it just makes sense to do the transaxle's output seal while you have the axle out. Most people don't even think of it. In your case, if there is any doubt about the cam seals now would be the time to replace them as you're almost all the way there. Since it's an interference engine where the pistons will bend the valves if the belt brakes I always recommend the idlers and tensioner for the timing belt every time. Again it might not be necessary, but for what damage could happen I feel safer with new gear in there.

As for the water pump, I'd personally rather replace a perfectly good one while I have the tools out and belt already off then have to go back in there in 30K later when it starts to leak. For around $60 I just sleep better.

Synthetic oil is the only thing you should be using. The engine is designed to run on it so it's the best way to go. Most climates the recommended weight is a 15W40. If it's the cost, try looking for the auto parts stores sales where you get a bargain on a name brand if you buy the oil and filter together. Usually shaves off around $8 or so. Also orielly and autozone have house brand synthetics at a really good savings and they aren't much different than the name brands. But ,,, try to stay away from Fram filters. There have been a number of people (myself too) who have had issues with lifter noise on start up when using Frams. The check valve that should hold oil in the engine and allow for faster pressurization of the system seems to not work that well.

These guys actually test the different oils:
O'Reilly Full Synthetic 5w20/5w30 - Bob Is The Oil Guy

 

Thanks so much for the varying degrees of opinions on this. I would also be more of a "while I'm in there" kind of guy if it's easy to do. Given that the TB replacement is a challenge to me, I'd like to (on this one) be "change only what it is needed" kind of person as it reduces the risk that I mess things up

I checked the TB area more closely last night. Good thing is that there are visible white marks on the CAMs, so that'll help. In terms of leaks. Water pump looks dry. So do the CAM seals interestingly. The rear cam seals have some oil build up, but the front ones are dry, even put my finger through there and was clean.

The only area where there is some oil is bottom left when you look at the TB area. So when I put the cover off, the bottom left of the cover also has oil. I think it's where that tensioner goes that has that push pin thing. But I doubt that tensioner leaks oil itself. Maybe it that mean the crank seal (which I could not see, seems like I need to take more things off to check it) is the culprit? It may just be old oil and no current leak so I will definitely clean it and drive for a week as suggested. Is it OK to just spray engine cleaner on the whole TB area when cover is off?

Also, what do you guys think in terms of the kits @FCP. Go with OEM (slightly more expensive) or is the aftermarket kit OK quality wise? I think it uses GMB tensioners. Welcome your feedback / experience. I need to fix some other things on this car (CV boots / axles), so keeping it cheaper where it's OK is great, as the total parts bill will already be high

 

Here is my real deal. You are saving a lot by doing the work yourself, about 60%. So, if you can afford to replace EVERTYTHING and have the SKILLS to do so, go ahead and do it all. Now there was a thread a week or so ago where a guy decided to replace his own cam seals, which turned into a HEAD JOB. So, he made a costly mistake in doing the cam seals. If he would have had the skills to do them himself, he would have been fine. Seeing that he didn't or made a mistake, he would have been better off paying a pro to do the seals. So, I don't usually encourage people to do the "extra work" when there is nothing wrong with the other parts and they will likely not even have the 17 year old car when the parts fail in 4 to 6 years.

If you can afford it, do it and have fun doing so. But if you lack good skills and are a little tight on money, do what needs to be done.

 

You may also want to check for parts here (great prices at a dealer):
TradeMotion Online Automotive Parts Catalog Software and E-Commerce Solutions

 

I hear you loud and clear, rspi. I think I'll stay away from the seals and waterpump. In terms of the tensioners, OEM parts only or aftermarket OK? What experiences have you had with the "cheaper" kit?

 

Presently doing my timing belt because there is no history of when it was done last. Pulled it off last nite and it looks great but I always put new parts on when possible.
Replacing the tensioners as well with new ones. I pulled off the water pump as well. It wasn't leaking but once again I feel better with all new parts in there. Every one has their preference, I'll do the water pump at every timing belt change.

As far as oil, I use synthetic in all my vehicles. I've read in the past where it doesn't break down as easy. And using the SOMP meter, (seat of my pants), my vehicles seem to run better when I use synthetic. Costs a bit more but to me it's worth it.

 

I will use anything that iPd sells. I trust them. I always use OEM parts when I can afford them. I will say that I am afraid of the newer hollow idlers that I see. I like the solid style rollers like used on the tensioner.