Oil for Volvo P1800?

[Hokiefyd]

A co-worker has a 1970 Volvo P1800E, with Bosch D-Jetronic fuel injection. It's been sitting for years, but he's got it at a shop now to have it made road-worthy again. They're doing a few thousand dollars' worth of work, including replacing many fuel system components, exhaust, brakes, etc.

The shop changed the oil and filter just to get the engine running, so they have a baseline, and they'd know what it needed. The repair order listed a PL14670 filter (this is the PH-16 size filter I think). They also listed "20/50 Valvoline".

He'll get the car back with a fresh oil change probably, but what do you all recommend he run in this car? He's not all that oil savvy, and he doesn't even know to ask this shop what they'd recommend. But apparently, it'd be some form of 20W-50 because it seems that's what they stock. I'm not sure that's the optimal oil for this engine.

I don't even know what the original spec was. The octane requirement is 98 octane. So I suppose the oil requirement could be similarly odd (for today's standards anyway).

Thanks for any and all advice.

 

[addyguy]

Nice car. Had a neighbour years ago that had a P1800 that used for car shows. It was in perfect shape, and a beutiful car!

I'd be inclined to use a quality 15W-40 or 5W-40 HDEO in that engine. I don't thionk those engines are hard on oil, but a HDEO covers everything.....

 

[coffee]

How many miles are on the car? That is a very nice car and if the miles are high you could go with a good HM oil of 10w40 grade. They tend to be quite robust and will help with an older vehicle.

 

[Johnny]

I would use one of the High Mileage oils in a 10W-40 or a 15W-40 in the P1800. I worked at a Volvo dealer back in the 70's and we used 20W-40. I see no need for a 50wt oil in the P1800.

 

[addyguy]

Originally Posted By: Johnny
I would use one of the High Mileage oils in a 10W-40 or a 15W-40 in the P1800. I worked at a Volvo dealer back in the 70's and we used 20W-40. I see no need for a 50wt oil in the P1800.


.....but Irv Gordon runs 20W-50 in his....!

 

[Johnny]

Originally Posted By: addyguy
Originally Posted By: Johnny
I would use one of the High Mileage oils in a 10W-40 or a 15W-40 in the P1800. I worked at a Volvo dealer back in the 70's and we used 20W-40. I see no need for a 50wt oil in the P1800.


.....but Irv Gordon runs 20W-50 in his....!




.....well, if I owned one I would use a 15W-40, then you could say .....Johnny runs 15W-40 in his.....!

 

[addyguy]

Yes, yes I could!

I was trying to make a joke to the effect that 'Irv gordon runs 20W-50 in his, and HE'S got 2+ million miles on it, so that proves that's what you should use!'

 

[Johnny]

I understood the joke as I was also making one. I just wish I had a 70's P1800.

 

[artificialist]

Research Octane Number and Motor Octane Number tend to be different from each other with RON being higher, and in the USA, octane rating is the average of the two numbers. Volvo might be calling for 98 RON fuel so it may mean 93 octane gas is acceptable. I don't really know.

I wonder how well Bosch D-jetronic works with E-10 gas, since there is no O2 sensor to control fueling.

 

[gaswrench]

Like open loop.

 

[dnastrau]

Originally Posted By: artificialist
Research Octane Number and Motor Octane Number tend to be different from each other with RON being higher, and in the USA, octane rating is the average of the two numbers. Volvo might be calling for 98 RON fuel so it may mean 93 octane gas is acceptable. I don't really know.

I wonder how well Bosch D-jetronic works with E-10 gas, since there is no O2 sensor to control fueling.


That is correct; in 1970 gasoline octane was listed as Research octane in the US. We switched over to the "Research+Motor octane/2" method in the late '70's if memory serves. Most other countries still list octane using just the Research number like we used to do which is generally 4 to 5 numbers higher than our current R+M/2 number. So 1970 "98 Research octane" gasoline is equivalent to the 93 R+M/2 octane yellow sticker on the pump today.

Andrew S.

 

[Pablo]

15W-40 will do nice.

If she's sealed up well a synthetic 15W-40 will do really nice.