Lubrication required for 2006 T5?

[PeterS60]

Yes, he's going to do a return line.

BTW, I asked for a flashlube (as he initially said that Volvo engine shouldn't need one); I read in this forum that a turbo engine should have an electronic kit, but both the installer and the shop supplying the parts told me that the effect is practically the same with the standard flashlube kit. Anyway, I hope they're right and that I won't need to travel to North Wales to have my installation fixed after few months :-)

[classicswede]

The normal system needs suction to supply the oil. In a turbo engine you will only get any feed on lift off and idle or very low RPM with low load.

The electronic kit is pressurised and doses off rpm signal so delivers the oil under all loads. This system is also favoured with non turbo engines that suffer especially badly. With some of the worst engines under high load the fuel can be split to about 10% petrol and 90% LPG.

I have experimented with the original valve saver systems on turbo's before the electronic systems came out. By using a balance pipe and some valves you can make the system work under vacuum and boost conditions but if fiddly to setup and does need tweaking very now and then to get the flow right.

The first you will know of the VSR problems is fuel trims drift then followed by uneven idle and poor starting. By that point you are into cylinder head work to fix the damage.

[skyship007]

Originally Posted by PeterS60

Hello everyone. I'm about to have my 2006 S60 T5 (260bhp) converted to lpg. I read about the valve seat recession issue and the lubrication to prevent it, but was advised by the installer that it is not required for Volvo engines. However somewhere else I read that valve seats in post-2002 Volvos are not so hard anymore, so the lubrication may be required. The car has done only 35k miles, but from May I will be doing around 20k miles a year and I plan to keep the car for few years. Could you please advise if I should have the lubrication system installed? Many thanks.

Considering how old this car is, it might be an idea to sell it and buy a diesel. LPG knocks the block life expectancy in half. A serious HDEO plus Ceratec might make more of a difference than a pre lube system. If the car is kept in a garage or within range of a power cable, another block saving idea is to fit a 250W sump heater pad (About 75 quid for the pad kit). That won't help the valves, but it does reduce ring and cylinder wear.

The final bill for the conversion plus the special lube system might cost more than a high mileage S60 is worth, although the LPG fans seem to think a pre lube is not required for older Volvo cars.

[classicswede]

What do you mean LPG knocks the block life in half?

If you mean the bottom end LPG actually extends the life 2 or 3 fold over petrol. The main reason for the extra life is the oil does not get contaminated allowing the engine oil to do its job for much longer.

[skyship007]

Originally Posted by classicswede

What do you mean LPG knocks the block life in half?

If you mean the bottom end LPG actually extends the life 2 or 3 fold over petrol. The main reason for the extra life is the oil does not get contaminated allowing the engine oil to do its job for much longer.

Sorry I should have said upper cylinder life, as it causes a lot more valve failures. I agree that the bottom end might well last longer.

This seems to be a good guide as to which engines are suffering from Valve issues under 100K km:
http://www.amrautos.co.uk/database_problem_cars.pdf
(It also lists the types that seem to suffer from injector module faults)

[classicswede]

The Prins list is not reliable as a lot of engines on that list with other systems do not suffer with VSR. For example the very common Jeep 4.7 does not suffer when fitted with kits with ECU's like AEB, KME or even stag yet with prins , AG or Piro they have problems. The Vortec is another engine that you will not normally see any problems with unless converted on one of those systems.

There is discussion on the LPG forum as to why that is the case but in short it is connected to how the injectors are driven and how the fuel maps are created. The Piro is an injector driver issue

It does look like Prins are having problems with the load simulators as most other systems are fine on most of those cars and the ones that do cause issues are easily fixed is an extra plug in box.

The fuel pressure issues with are easy enough to fix when you know.

Valve train life comes down type of valve lifting and materials used.

[skyship007]

Originally Posted by classicswede

The Prins list is not reliable as a lot of engines on that list with other systems do not suffer with VSR. For example the very common Jeep 4.7 does not suffer when fitted with kits with ECU's like AEB, KME or even stag yet with prins , AG or Piro they have problems. The Vortec is another engine that you will not normally see any problems with unless converted on one of those systems.

There is discussion on the LPG forum as to why that is the case but in short it is connected to how the injectors are driven and how the fuel maps are created. The Piro is an injector driver issue

It does look like Prins are having problems with the load simulators as most other systems are fine on most of those cars and the ones that do cause issues are easily fixed is an extra plug in box.

The fuel pressure issues with are easy enough to fix when you know.

Valve train life comes down type of valve lifting and materials used.

I agree with that, BUT valve train life depends as much on the degree to which fuel cools the inlet valve (I don't think it's so important for the exhaust valve) and that does vary with engine design.
To give you an example the V50 does not drop valves, but is on the list for failures within 100K km. Ford may have back specced most of their main bearings, but as far as I am aware none of the majors have been doing that with valves as it tends to result in too many casting faults that are difficult to detect. Some of them have reverse engineered the quality of the steel used in the cams, but after the issues VW had, I doubt if any of the majors have done that.

The other issue is over the cost of repairing a damaged head, as Volvo don't do Recon units. To stand any chance of lasting another 100K km, it would need a new head and a good one is real expensive. I was also surprised to read that the Flashlube system does not prevent valve issues as well as I thought it did.

[classicswede]

If there is a problem there regardless of the fuel used then Flashlube is not going to be able to prevent VSR. There are a lot of Ford engine (and others) that have problems on petrol with the valves sinking back into the seats so the problem will be far worse on LPG. Flashlube will help but as the materials are so soft that its going to happen eventually anyway.

In most engines that suffer VSR on LPG without any protection its normally only the exhaust valves that cut back. As the inlets do not have as much heat to deal with and are cooled by the intake charge they normally last ok.

Should you suffer VSR then its no big deal. Very mild cases can be fixed with a recut and adjusted clearance while worse cases can be delt with by fitting new seat and valves. In most cases this will only be on the exhaust side.

The cause of VSR has nothing to do with cooling of the valves or at least any cooling is only a tiny factor. The biggest part of the problem is the super clean burning so there is no carbon between the valve and seat to prevent or reduce the micro welding. Engines with variable cam timing tend to have faster valve closing speeds and are much harder hitting. The harder impact makes the problem worse, if you do research on the compromises made in materials for VVTI engines you will see why they have problems.

Some systems allow a trickle of petrol to be added to the mix and this can be a useful tool with engines that have the worse problems.