Hydraulic lifters, a warning.

[Rosieuk]

My car has the 1341MPFI 12v Alpha engine - not a bad little unit (apart from the unmodifiable ECU). However it does have two potential nasties. It has a 50,000 mile cambelt and it has hydraulic lifters.
With the latter, do not deviate from manufacturers specs for oil and more importantly make very sure a garage doing a service doesn't. You will get all sorts of weird problems and more importantly you will knacker your lifters & valves without the right oil viscosity. Luckily I got away with it with the Accent, but it's still not perfect (replaced most of ignition system, idle air bypass, TPS before the problem was identified). In addition the garage mashed number 4 injector cable replacing the idle controller..
If it runs long enough like this you will need new valves, lifters at best, a new head (valve seats) at worst. Not to mention all the metal shrapnel politely introducing itself to your bearings etc.

[oil pan 4]

I have found hydraulic lifterse to be very robust.
The only thing I can think of that would really mess with them is putting oil in that is way too thin, not allowing then to pump up as they would with the proper oil.
Oil that is too thick won't allow them to leak down at low speed.
I run 5w-40 oil in pretty much everything so I wouldn't have this problem.

[Rosieuk]

Got it in one, that's exactly what the "trained mechanics" did to my car and it took me almost 6 months and a lot of expensive (unnecessary) parts to figure out why it was idling like a cement mixer and had all the get up and go of a beetleback Vanguard.
But there are a lot of "thinner oil" suggestions for economy and not once are hydraulic lifters mentioned so far as I can find. The Alpha engine requires either 10w30 or 10w40 for the lifters to work properly. 10w30 is the absolute minimum.
That said I think I've escaped serious damage - did 44.73mpg, today, over 93 miles in winter which is better than it should (44mpg mixed) by some way (I mostly do very short journeys (4 miles)) and adding about 15% for summer mileage is a healthy 51-52. 8mpg over advertised.
Incidentally I've a transparent plastic grille block on (leaving rad fully clear, it's marginal at best in size). Looks a lot less obvious (important with our local police).

[LittleBlackDuck]

Originally Posted by oil pan 4

I have found hydraulic lifterse to be very robust.
The only thing I can think of that would really mess with them is putting oil in that is way too thin, not allowing then to pump up as they would with the proper oil.
Oil that is too thick won't allow them to leak down at low speed.
I run 5w-40 oil in pretty much everything so I wouldn't have this problem.

I agree that the lifters are very robust and unlikely to be damaged by the wrong oil viscosity.

There is a plethora of other issues associated with changing oil viscosity that can be very damaging to the engine. As the original poster said, too low viscosity will prevent the lifters from working properly, and in this case they will fail to control the valve lash. This can cause lifters and other valve train components to be hammered to death. Conversely, too thick oil will cause the lifters to pump up and keep the valve open. Consider high load and an exhaust lifter pumping up - burnt valves here we come. If they pump up enough, you could get valve to piston interference.

Older engines can be much more tolerant but newer ones have much tighter tolerances.

Simon

[ThermionicScott]

What did your garage use?

[Rosieuk]

They used 5w30, not thin enough to cause instant damage - but enough to, over time cause niggling issues with idle at first and then symptoms like misfiring, but not. Then mpg started to fall off.. Dealer wanted to pull the head, £450 just to look.

I strongly suspect they've been shoving it in anything that comes in rather than getting the proper stuff in, but I can't prove it.

I've got a suspicion it's not done the mains any good either but I don't have the money to have someone tear it down. It sounds suspiciously like my first Humber that had a hot oil pressure of 5! when it's half warm at idle. Still the Alpha was supposed to run 21psi hot so it's not as bad as the Audax engine, that was supposed to be 50psi @ 3000rpm.. Not 5.

Had a nice fast run this afternoon though, 65-75mph & still averaged 12l/hr.. Previously that sort of run would have been 14-15. I don't think it was too serious. But people need to check that what they're getting is what they asked for, and know what they need.

[skyking]

My toyota was messed up by oil too, going the other way. It ran 5w30, and one day I had a case of 10w40 and decided to just put that in :Facepalm:

About halfway through that oil interval, I got ticky lifters. I dumped and changed it to the 5w30, and about halfway into the next interval it went away

[me and my metro]

Old Mazdas are very particular about the correct oil as are Geo Metros.

[skyking]

the 'yota gave me that one lesson, and never made that noise again. I learned