1998 s 70 t5 cold start whining engine noise

[headshot10]

Jeff, Further to my earlier correspondence, believe have worked it out. Location of solenoid valve is directly in front of trans dipstick and is referred as item 24, 9135444, valve. On the manifold side of this valve is what we believe you indicated as the check valve, referred as item 23, 1275794, valve and as depicted by EVAP parts diagram. The referred valves are not encased in the foam rubber as you indicated, could it be that 1996 model had them just mounted to the top and rear of the radiator fan shroud? It is interesting to note that the EVAP parts diagram does show the solenoid valve encassed, though the components fig. numbers are not listed. Will undertake testing over the next couple of days and report findings to this thread. Thanks, Barry

[toolmanjsp]

Hi Barry,

My cars are US spec, left hand drive. I have a 94 sedan and 95 wagon, on both the EVAP valve is encased in a cylinder of foam rubber mounted by a clamp to the fan shroud in a location of the engine oil dipstick. It could be in later years and in the 70 series the valves were left exposed, I must admit I don't know as these two 850s are the only Volvos I've ever worked on, but by now it seems like I've almost overhauled both from ground up. It is the sedan that has given me the most problems, the wagon has had the least maintenance, has the most miles, and has given us far fewer problems while we've owned it. Strange how that works out sometimes.

I do know that they further modified the EVAP lines in later years to include a "T" fitting in the line between the charcoal canister and the EVAP valve, the "T"'d leg going through yet another of those gray check valves then into the snorkel between the air filter and turbo compressor inlet.

This was probably to allow a little bit of purging to go on even when the EVAP valve was closed or the engine was under boost, just guessing here, but that is what it would do.

Good luck and let us know what you find out!

Jeff

[fields 100]

The evarorator (purge) valve is located under the fan shroud cover next to the SAS solenoid. As you mentioned before, the sound comes from the front camshaft bearing (in my case- intake camshaft, with a stethoscope). The puzzle is that it DOES NOT sound like the bearing noise. The most accurate description in my case (and that is the best I can describe) would be the sound of the wine glass when you move wet finger round and round the rim. It is some kind of higher pitch moan.It comes up and goes away several times until temp. needle at about 4 o'clock. You mentioned possibility of cooling issue: could it be sound of the cold coolant going through the partially stuck open thermostat? Understand that it sounds pretty farfetched, but I am running out of options on this issue.However,the whining noise I mentioned in the beginning of this thread went away when I changed to Castrol Syntex 5W30. Thanks.

[voltech1]

I would not worry about the warbling noise. They (5cl) must all do this. When I lived in Florida mine did it EVERY morning. It seems to be more related to temp/humidity. I have never had another tech be able to tell me exactly what it is but my guess is the oil pump cavitating. I have never had my oil pan off to check the sump o-rings. Pick up tube o-ring sucking air when oil is still thick?

[fields 100]

But the sound comes from the top of the engine (sound transfer?). Oil pump and pick up tube are good possibilities, however the car has only 42K( noise came at 40K) and I am the first owner. You think it is possible with such low milage? Thanks.

[headshot10]

Jeff (toolmanjsp), undertook the following works over the past couple of days relative to EVAP circuit and in an attempt to establish whether this circuit was contributing to the noise referred previously within this post. It must be stressed that these works were not as a result of any warning light and/or fault codes and the results have been included here as an aide to other forum members.

Removed both EVAP solenoid and check valves, stripped and cleaned solenoid valve with solvent as per instruction at https://www.matthewsvolvosite.com/forums ... =1&t=31691. Even though there was a difference in valve design, the principle was common. Cleaned the check valve with solvent only, tested and held vacuum, refitted both valves and fitted new hose between check valve and manifold as showing degradation. Internal condition and cleanliness of both valves was excellent.
Connected a vacuum gauge between check valve and manifold, ran up engine in static mode and typical vacuum readings (in/hg) indicated. As the engine was warm from earlier run, there was no evident of noise referred within this post.
Next connected the vacuum gauge between solenoid valve and EVAP canister and road tested at a fairly consistent 100 kph (62 mph) for ¾ hour with the following indicated.
• System is loosely controlled by way of a 6 minute and then a 2 minute cycle.
• During the 6 minutes, unless accelerating or on a closed throttle, the vacuum gauge fluctuates between 0 and -5 in/hg (vacuum) and 0 and + 2 in/hg (pressure). Estimate this fluctuation would be about 5 times a second.
• After this period the gauge would hold steady on 0 for some 2 minutes, regardless of throttle position and then the cycle would repeat itself.
Again, we reiterate that there were no warning light and/or fault codes prior, or post these works. Next morning, with ambient at 18ºC (64ºF), started vehicle, no evident noise. Whilst it was not the result we were looking for, identified some vacuum hoses that needed replacing.

fields 100, thanks for your feedback re thermostat and which we comment. Only a month back changed water pump and coolant and at start up used a temp gun to watch the temperatures around the engine bay. It was clearly obvious when the thermostat opened, hot water purged through and then thermostat closed again once cooler water from radiator/block was sensed. This cycle continued, opening and then closing, as is expected by design. Whilst not completely discounting coolant circuit, has now been moved down the list a little. Relative to the noise, you are correct re wine glass, though at times it sound exactly like a dry bearing (ball/roller) that has seized and then started rotating again, similar to that of a failed cam and/or serpentine belt rollers, though we know it is not that!

voltech1, thanks also for your feedback. Whilst we do get down to 0ºC (32ºF) once or twice a year in winter, (June-July) our usual morning temp is between 8ºC (46ºF) and 18ºC (64ºF), not what one would call cold and nothing that SHOULD cause a major change in oil viscosity, resulting in cavitation. Notwithstanding this point, the scenario of engine oil cavitation and/or chattering over relief is now high on the suspect list. As previously indicated, oil analysis does not indicate detrimental elements (iron, copper etc) being indicated. Could you please expand upon your thought re oil pump cavitation. Same grade of engine oil has been used for 15 years. Ambient temps have not changed. Noise has only been evident for some 12 months. What would be the cause/effect of o-rings you referred? Why would o-rings suck oil when oil was cold (more viscous) than when hot? Will endeavour to locate a schematic/exploded view of the oil pump/lubricating circuit and study the components further.

Thanks for everyone who has taken the time to respond and please keep the thoughts coming, whilst, perhaps not detriment to the longevity of the car, very annoying not being able to solve. Finally, car is run predominately on unleaded 95 and 98 octane fuel, injectors have never been out or serviced after 269K+ klms (167K miles). As indicated within this post, noise is also indicated under inlet manifold, from your experience what could be in or around the PCV valve which, may exhibit the noise?

Barry

[kcodyjr]

Could it be coming from the valve train or camshafts themselves? If your oil sump seals are bad, or oil pump is failing, or if you're using an oil filter without a check valve (Fram orange can of death), then it's just taking awhile for the oil to reach the top of the engine. It would neatly explain the cold-start-only part of the problem.

[headshot10]

kcodyjr, thanks for feedback. As previously indicated, since new car has been on Mobil 1 and genuine Volvo oil filters, changed regularly at approx. 7.5K. Max oil change interval was some 8.5K due to Nullarbor crossing to East coast. Engine oil is sampled every second oil change and to date there are no elements indicating wear or degradation within the engine. All of the scenarios you have referred result in elements (iron, copper, lead etc) being reported within the oil sample analysis. Thanks again, Barry

[kcodyjr]

No elements would turn up if there's no actual abnormal wear; bad oil sump seals would just make the pump cavitate until the oil warms up and flows more freely. You're right that it rules out a worn oil pump.

There will be a thin film of oil on every surface even after most has drained back to the pan, so I can see an ongoing cold-state oil pickup problem not causing physical wear.

These engines have a set of rubber oil sump seals that can degrade over time, and would look pretty much like the rest of the oil under mass spectroscopy. It all came from the same dinosaur juice.

[fields 100]

Barry, I think to eliminate the issue with a pump, one should drain the oil in the evening, let the engine completely cool off, and next morning fill the engine with a fresh, HEATED elsewhere oil and go for a spin. There will be cold engine filled with warm oil.See what happens.Can not grade it as 100% scientific approach, but it may very well put us both out of our mental misery. I am going to try it myself, time permitting and keep posting. Thanks.