Diesel Engine Oil in D15B4 petrol engine?

[90civicGL]

Hey guys, at the moment my car releases a tiny bit of black smoke when letting of on the accelerator when in the 3-4000rpm range, I am fairly sure that the valve guides are worn. But haven't done any real investigation.

It has old oil in it at the moment (havn't been driving it currently not registered just turned it on a few times to investigate other issues, but before I continue further I want some good oil)

My dad has offered me free oil if I can use it, and free oil is good oil. It's what he uses for his hilux, but he suggested it would make good oil for my engine since it is on the older/worn side (414,000k's) It is CH-4/SJ rated 15W-40 oil. It is my understanding that SJ is the petrol rating for it. The owners manual for the car says "Use SF or SG grade detergent oil only"

It is my understanding that if I can use SG then I should be able to use a higher oil like SJ correct?

The oil is "Hi-Tec Oils, FLEETMASTER 15W/40" "Meets SAE and API CH-4/SJ spec"

Please only answer if you know the subject, dont just read diesel oil in petrol engine and jump to the conclusion it can't be done, as to my knowledge it can be done if the ratings match up. Just want a second opinion as I am not very familiar on the topic.

Thanks.

[90civicGL]

Decided against it as there are mixed opinions about it online. Just going to get some of that castrol 20W-50 GTX oil designed for old engines. Will run that while I am going for roadworthy. Then next oil change probably put in some 10/15W-40 petrol oil.

[dougie_504]

Just change the valve stem seals/guides or w/e.

20 weight is quite thick for a cold engine, I'd have recommended maybe a 10-50 like the Penrite HPR 10 full synthetic with zinc additive included.

Or a mineral oil.

[Daveho1]

at the moment the best oils are an SN rating and the gtx 20-50 was the correct way to go IMO best 20-50 out there with out moving into synthetics which your engine dosent need, trust me that gtx20-50 is the best bang for buck you could have gotten. i worked for super cheap for years and had the oil catalouge memorized

[trism]

Diesel oils have more detergent additives in them because a diesel motor is runs dirtier. Extra additives assist in keeping the cylinder bores clean so that gouges dont occur, because a diesel relies solely on compression to ignite.

If you run a diesel oil in an old worn engine, theres chances you could make the smoke blowing worse.

As it circulates through the motor, itd clean all the old gunk and shiz and probably make nice big holes for oil to blow through.

[cbauto]

at the moment the best oils are an SN rating and the gtx 20-50 was the correct way to go IMO best 20-50 out there with out moving into synthetics which your engine dosent need, trust me that gtx20-50 is the best bang for buck you could have gotten. i worked for super cheap for years and had the oil catalouge memorized

its d15b. needs the best oil money can buy