no compression in cylinder #3, 1998 V90 L6, 24 valve engine

crosscut123 · Post by **crosscut123** » 26 Jul 2007, 21:05

I've recently acquired a 1998 V90 in otherwise good condition; engine runs, but there is no compression in cylinder #3. Can anyone give me a start as to what to look for and the possible problems I'm faced with? Thanks in advance. Crosscut123

volvoaddict007 · Post by **volvoaddict007** » 27 Jul 2007, 12:34

More info please:

Mileage on motor. I'm assuming no compression mean 0 lbs. or is it just very low and if so how much and how much in the other cylinders. Did you acquire the vehicle with this condition or did something happen preceding it i.e. overheating, overrevving etc? Any other symptoms? Have you checked for coolant in the oil? Is there any noticeable blowby ( smoke coming out of the dipstick tube) With the engine running do you feel a slight suction at the dipstick tube or does air seem to be pushing out

va007

volvoaddict007 · Post by **volvoaddict007** » 28 Jul 2007, 12:22

deleted

volvoaddict007 · Post by **volvoaddict007** » 31 Jul 2007, 03:46

crosscut123 wrote:I recently acquired a 1998 V90 with 125 K miles on it. It has the 2.92L (3L?) L6, 24 valve non-turbo gas engine. Owner's manual says that cam belt was replaced at 70K. Engine has a miss that I have diagnosed means it probably has a burnt valve. 0 psi in #3 cylinder, 190-195psi in others. Oil injected into cylinder #3 doesn't change psi. No blow-by to speak of. I assume I will have to remove the head and replace one or more exhaust valves. Is this something an enlightened amateur should attempt? I have rebuilt several traditional engines in the past, but nothing like this one. I'm waiting for a workshop manual to come, but in the meantime, what little information I am gleaning from hints on the web make me think that volvo has made repairs harder than they need to be, with numerous ridiculously expensive special tools and a reticence from dealers for sharing any information. I also read that volvo doesn't make replacement valve guides for this engine anymore and requires repairs to be made with factory-rebuilt heads. Since I'm assuming that I might need to replace a valve guide or two, what's that mean...just buy a replacement head and throw the old one out? When I buy a rebuilt head, am I likely to get a complete head, or just the core...and I have to replace the valves and cams, and ?? Anyway, some advice from experienced hands would be appreciated before I go past the point of no return on this car. Thanks in advance!!

Compression on the rest is great! Sounds like a valve is stuck open for whatever reason.

I am suspecting your problem will be determined once a valve cover comes off.

Since you are willing to do a head replacement this is the first place I would look.

I'm betting on a dropped valve, collapsed ( broken )valve spring or (askew or broken ) rocker arm although I am unfamiliar with this motor.

Either of these scenarios may require a cam R & R at the worst.

Especially since this is a rear wheel drive vehicle, instead of going through the headache of a head replacement ( if needed ), I would tend to go to VOLVO and SAAB Auto Dismantlers in Sacramento, CA or another reputable VOLVO salvager and buy an entire used motor. V&SD will gaurantee a motor 90 days or lifetime for an additional charge as well as asking for your vin# to assure the proper replacement. They also will tell you mileage and compression on the prospective motor. A motor delivered should cost about $900. Do the timing belt, water pump, rear and main seals while you're in there

I've aways felt that heads and blocks together from the factory are your best bet.

They could have a motor with fewer miles that adds value to your car at the same time. That car all cream puffy should bring at least $5000 - $6000 on the used market.

va007

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The following are replys at this juncture from related thread: 1998 V90 Want to repair/replace cylinder head..am I insane?:

Major problems with taking off the head and replacing it include:

They invariably have to be skimmed.

You need all new cylinder head bolts at a mega-price.

Valve guides are still listed but, apparently, in short supply in the UK so I would assume the same in the US.

va007's suggestion has great merit.

Bill.

and...

Why thank you O Great One.

I'd put a short piece of garden hose on that valve cover over #3 ( like a stethescope ) and listen for something unusual. I overrevved a Saturn motor once and the dealership claimed nothing was wrong with it when there was an obvious miss. I had that particular valve cover off in 5 minutes and there was a rocker arm that had just popped off and was laying there. I popped it back on with a screwdriver and a pair of vise grips and was good to go.

Hey Bill, I'm unfamiliar with a V90 valve train but isn't there some sort of retaining clip ( a C-clip ) that holds those valves on and maybe someone at the factory...or for whatever reason, it broke or fell off?

That's my best guess.

OK crosscut, now I'm curious. Get that daggum valve cover off o' there and report back

va007

crosscut123 · Post by **crosscut123** » 01 Aug 2007, 07:49

Dear VA007-

You say to avoid the headache of Head replacement I should replace the engine? Is that really a better option? I would think it would be cheaper/easier to replace the head! ($500 for a reconditioned head from several rebuilders). Also, I was thinking , because of the dearth of reputable shops around here, that I would attempt it myself...but the head is one thing, an engine replacement something else...
I have looked up several salvage companies' websites and found the used engine prices are more in the range of $2,200 - $2,900 plus shipping. That is the price from Volvo and Saab Dismantlers in Rancho Cordova, CA ...are they the ones you referred me to?
I have had several mechanics express the opinion that on a worn bottem end, putting a new head on will cause them to, as one said, "blow out the rings" This is counter-intuitive to me, as I cannot think as to how the replacement of one head for another will change anything as to compression, etc. Do you have any experience with this stated phenomenon...and an opinion? Thanks again for all your advice!!
Crosscut123

volvoaddict007 · Post by **volvoaddict007** » 01 Aug 2007, 15:22

crosscut,

BEFORE DOING ANYTHING ELSE, take the valve cover off of the current motor. You may have a problem that is REALLY EASY to fix.

My guess is that you are going to be able to fix your problem w/out a head removal.

Because the compression is so good in the rest of your motor I don't feel that you need to recondition the head, just repair the valve.( Assuming this is the problem. You won't know untill you TAKE THE VALVE COVER OFF!

)

The mechanics are correct that in a WORN motor, to bring all kinds of compression from a rebuilt head to the bottom half will tend to seek the weekest and now unbalanced link. I'd say the biggest threat is to the rod bearings where a little slack can be handled along w/ a loss of compression.

IF you told these mechanics that you had 190 ft. lbs in #s 1,2,4,5 and 6 and they told you your bottom end is worn they may be looking for a rebuild. Then A FEW mechanics may just put it back together and TELL YOU they rebuilt it. Mechanics unfamiliar with VOLVOS may think 125k means WORN MOTOR. Hell, that motor is just breaking in!

I called VOLVO and SAAB AUTO DISMANTLERS in Rancho Cordova, CA ( East of Sacramento ) 1-800-VOLVO (8658 ) or 916-635-9970 and spoke w/ Kenny.

He told me a V90 engine for '98 is $1200 + $300 to ship to North Carolina. My prior guesstimate ( $900 ) was based on my 850 T-5 motor shipped to southern California.

You should be able to find a mechanic that could do this job for $500- $1000. It's a 1 day job...TOPS

R & R ing a motor on a rear wheel drive vehicle takes less expertise than replacing a head.

Now you are going to have to consider: $1500 for car $1500 for used motor,$300 for waterpump,seals and timing belt. $1000 labor.= $4300+

With the higher than expected cost of the motor. Repairing the head is looking like a toss-up ( a coin, not your lunch ) but you won't know until you take the valve cover off.

Before I spent that kind of money I'd get a CARFAX if you haven't already to make sure this cars history is clean and you're not throwing good money after bad.

Let me know what you find under that cover .

va007

crosscut123 · Post by **crosscut123** » 02 Aug 2007, 14:36

Dear VA007-
In the course of talking to a number of shops around here, one of the things 3 of them mentioned was the special tools needed to do the head job, like locking the cams in place... and the one that really got me concerned was the one that one mechanic says was used to compress the top half of the head to the bottom half. He said that one of the mistakes some mechanics who are unfamiliar with volvo make is trying to put the head back together without the tool, which evidently brings the top down over the cams smoothly and evenly-this evidently is needed to make sure the cams aren't bound up in their bearing races? Since I don't have the shop manual CD on this car yet (which I ordered from a guy in GB over ebay), I can't figure it all out, and whether he was just loading a bunch of manure on me or not. I haven't been brave enough to to go any further than compression tests. I don't know if I can bring myself to break it open if I'm unsure if I can put it back together. I have thought that MAYBE I would get in there and find a broken valve spring..and that it might be possible to repair it without disassembling the head...I've done that before by injecting pressurized air into the cylinder through the spark-plug hole to hold the valve in place while removing the pieces and re-installing the spring and keeper back on top of the valve stem. I just would be flying blind with this volvo, having very little idea of what I would be getting into beforehand without a diagram, (or better yet, repair manual and procedures). Do you have any thoughts about that ?
I HAVE been talking to local shops and the consensus on 3 of them (the volvo dealer will not give me a ballpark price) is that a head R&R will cost about $2500, including machine shop work, a new cam belt and tensioner, and all the gaskets, coolant, oil etc. They estimated a used engine install of $3800-$4000 if my engine is found to be no good. A head rebuild I can live with, because I get a car that will have cost me $4000 which ranges in value (Edmunds, Kelley, NADA) estimates from $5300-$7000, and which I will have pretty good confidence in. I have the CARFAX report, and even though I have no data from 2002-2005, the car remained in the same area it first was sold in, and I have checked it out fairly well and otherwise it seems operationally and visibly in good shape. What I might have a hard time with is spending what they estimate a replacement engine would cost. But I have not explored MY getting the engine and having THEM or somebody else put it in...if I can get an engine with comparable mileage for around $1500 and then sink another $1300 in repairs and installation, that might be doable. Add whatever they want to charge me for getting down to the cylinders and seeing that it needed a new engine- thats what, 1-2 hours shop time at most?
By the way, I want to thank you again for your willingness to share your expertise and opinions...and listen to my travails...it really helps.
crosscut123

Post by **billofdurham** » 02 Aug 2007, 15:43

Since I don't have the shop manual CD on this car yet (which I ordered from a guy in GB over ebay)

If this is the Mitchell On-Demand CD it is very helpful but, as it is taken from Volvo Cars US literature, it assumes that the reader has access to the special tools. The pictures of these tools are line drawings and not of any great value in assessing what each tool does. VADIS does show photographs of the 7 special tools needed. From what I can see there is only one that could possibly be made by the DIY man, the rest would need to be bought or hired. Not a practical proposition as the people most likely to have them are the Volvo shops.

As with the 960, cylinder head re-build is not really a DIY job.

Bill.

volvoaddict007 · Post by **volvoaddict007** » 03 Aug 2007, 08:00

...

... take the valve cover off... please.

I will be on the road for about 3 days starting Saturday afternoon and won't be able to reply during that time.

... va007

crosscut123 · Post by **crosscut123** » 06 Aug 2007, 20:03

Thomas-

I do not have the wherewithal to get the head back together if I
take it apart, and I decided to leave it alone and wait to see what the shop
discovers. Thanks for your support and advice, but I'll just have to go
with the judgement and trust the shop to tell me the truth.

Glen Davis