higher viscosity to use to decrease increased oil consumption?

[8292sbc8292]

Hello all. I have been using various 5w40 oils in an -87 5.0 TPI engine, in the past, but in the past years, since the engine is getting more worn as the mileage increases, total about 100.000-150.000 miles so far, (idk the accurate mileage since the odometer hasn't all the time functioned as it should), the engine has been consuming more oil. Would 5w50 or mixing 5w40 with 10w60 to get a thick side of 5w50, be a good idea? The engine consumes oil about a quart in every six months, its a daily driver so I usually keep adding a tad of oil every few weeks, idk how much oil it consumes at every 1000 miles since the odometer isn't always functioning. The car doesn't see many miles a day, sometimes just few miles a day, sometimes about 20-50 miles a day. The car gets driven in winter, but luckily the coldest that it sometimes gets at winters where I live, is only about 14Fahrenheit. I have nodest that sometimes theres nasty burnt oil smell like burnt BBQ coming from the exhaust pipe, to me its unbearable, so in the past I had to put a catalytic converter back in the car, luckily it helped with the smell, usually it doesn't smell at all, sometimes tho when the car is pushed hard in first gear, but the smell vanishes later on. At this point im not sure if the smell is caused by oil getting burned or if the engine is running rich/lean, and the cat is a temporary fix as it might get clogged over time, since the inside of the exhaust tip gets black of soot even after few miles. The oxygen sensor and the distributor cap, plugs, etc, has been changed according when ever its time for a tune up. My idea so far, when it comes time to change the oil, if I were to use shell helix ultra 5w40 and mix some 10w60, or Castrol edge 5w40 with 10w60. I´ve tried red line in the past, 5w40, and isn't that a thick side, almost 5w50? that didn't help with oil consumption, that's why I have been thinking if some 10w60 would be a good idea. Years ago I tried some STP blue bottle oil additive, it did help with the oil consumption but only for a month or so. The engine does not leak oil. I also change the pcv valve at every oil change to make sure the oil consumption isn't because of bad pcv valve. I usually change the oil and the filter with Purolator filter just before winter and again after winter, around April. I have never used seafoam and never heard of it cuz I have never seen it on shelfs here in Europe but I have always been curious to try seafoaming the engine/intake. The vids on youtube and the white smoke cloud is quite a show! LOL For months now, I've been using Valvoline MaxLife 5w40, and for the heck of it, a while ago added a bottle of Rislone valve seal repair to see if it helps with the blue start up smoke that the car has had ever since I can remember, tho it has indeed for years puffed some blue smoke at start up, even when the engine wasn't consuming oil many years ago, so I assume the start up smoke isn't related to the oil consumption, but its possible that the valve guide seals have worn more as the time has gone by, and these days play a part when it comes to the oil consumption, but for years even these days, it surprisingly does NOT puff blue smoke at start up if the car has been sitting over night, only when the engine is warm and has been sitting for lets say, 10 minutes or few hours. At the time being, I can´t afford to get the valve seals replaced, so any advice about what oil viscosity/additives (if the piston rings are stuck causing extra oil consumption) to use, such as MMO/seafoam/engine flush such as liqui moly or a tad of ATF to use at the next oil change, if it would be a good idea to try, would be appreciated. Thanks.

 

[Triple_Se7en]

You need interior engine work and that's normal for the vehicle age. I would use conventional oil in 15w40. Drop down to 5W40 for the mid-winters. Your consumption levels are not that high. One quart in what might be 4-5K is OK. Nothing drastic needs to be done.

 

[8292sbc8292]

Originally Posted by Triple_Se7en

You need interior engine work and that's normal for the vehicle age. I would use conventional oil in 15w40. Drop down to 5W40 for the mid-winters. Your consumption levels are not that high. One quart in what might be 4-5K is OK. Nothing drastic needs to be done.

Probably. If I recall correctly, the engine has been checked with one of those tiny cameras or what they are, according to a mechanic the engine would need new heads, bearings, something like that, because according to the mechanic, the engine is simply worn out, more or less. But im not sure if that much work would need to be done, the oil pressure is good with 5w40, around 30psi or above, at idle and higher at highway speeds, no smoke when accelerating, and the engine is making no strange noises, idles smooth and quiet. My own belief is that the only thing that would need to be replaced are the valve seals but idk, I could be wrong since im not a mechanic. As far as the oil goes, I would like to stick with full synthetic since over twenty years, the engine has seen nothing but full synthetic oil and im not a fan of mineral oils, but of course since the engine is three decades old, it doesn't matter what the oil is, it doesn't make it a new engine

 

[atikovi]

Originally Posted by 8292sbc8292

so any advice about what oil viscosity/additives (if the piston rings are stuck causing extra oil consumption) to use, such as MMO/seafoam/engine flush such as liqui moly or a tad of ATF to use at the next oil change, if it would be a good idea to try, would be appreciated. Thanks.

You can try a dose of Kreen if available to you, otherwise, just live with it. It's a 30+ year old car and most people would be happy if they only had to add a quart of oil every 6 months to a 10 year old car.

 

[Olas]

Try valvoline maxlife and be sure to keep it topped up. Pull the PCV line to check for blowby and you will have some info to help decide if it's valves or rings. Have you checked compression?

 

[Patman]

Keep in mind that the OP is in Europe, so a lot of the oils that people are going to suggest that he try are not available over there.

 

[RDY4WAR]

I've observed an increase in oil consumption when switching to a thicker oil in an engine with stiction problems as the thicker oil film increased the oil transport past the rings. Thicker oil isn't always the best solution. I agree with above that a quart every 4-5k isn't a concern.

 

[BigD1]

No decrease in oil consumption going from 10W-30 to 10W-40 on my 92 Toyota pickup. Still using a quart every 3,000 miles. What is odd though, and I have seen this mentioned before on this board. The first 1100 to 1200 miles on fresh oil it does not consume.

 

[burla]

I'd pull the plugs check each plug and the cylinders with a boro. Might do that after a sea foam through the vac lines use, don't watse your money putting it in gas tank. You may have a piston ring that is bagged beyond use, if it gets worse. The oil usuage rate isn't terribily disturbing, I have had engines burn more when new and throughout their life then that, and one of those was the best vehicle I ever had. For 11 years it burnt qrt every 3k miles off the showroom floor.

 

[8292sbc8292]

Originally Posted by atikovi

Originally Posted by 8292sbc8292

so any advice about what oil viscosity/additives (if the piston rings are stuck causing extra oil consumption) to use, such as MMO/seafoam/engine flush such as liqui moly or a tad of ATF to use at the next oil change, if it would be a good idea to try, would be appreciated. Thanks.

You can try a dose of Kreen if available to you, otherwise, just live with it. It's a 30+ year old car and most people would be happy if they only had to add a quart of oil every 6 months to a 10 year old car.

I don't mind about the oil consumption much, tho i've often thought that too much oil consumption causes deposits in the engine in the long run, but as far as the burnt oil smell goes, I wish it would consume a little less oil, perhaps then the burnt oil smell would disappear completely and I wouldn't need to keep the catalytic converter on the exhaust just that the exhaust wouldn't smell like burnt oil.

 

[8292sbc8292]

Originally Posted by Olas

Try valvoline maxlife and be sure to keep it topped up. Pull the PCV line to check for blowby and you will have some info to help decide if it's valves or rings. Have you checked compression?

I haven't checked the compression yet but i´ll keep it in mind. Do you mean that if i take the pcv valve off from the hose or the hose completely? How do i check for blow-by? I guess the engine might stall if i take the valve or the hose off when its idling, i remember it won´t start without the valve, but might barely idle without the pcv valve.

 

[8292sbc8292]

Originally Posted by BigD1

No decrease in oil consumption going from 10W-30 to 10W-40 on my 92 Toyota pickup. Still using a quart every 3,000 miles. What is odd though, and I have seen this mentioned before on this board. The first 1100 to 1200 miles on fresh oil it does not consume.

Have you done an oil analysis? Are you using full synthetic oil? Seems to me that perhaps the additives in the oil burn off or something like that, too quickly. I´ve used various oils in the past, some oils, even when the viscosity is the same, some oils tend to cause a drop in oil pressure just after a month or two, some oils keep a steady oil pressure even when hot, such as red line oil. Have you nodest a drop in oil pressure once the engine starts to consume oil?

 

[8292sbc8292]

Originally Posted by burla

I'd pull the plugs check each plug and the cylinders with a boro. Might do that after a sea foam through the vac lines use, don't watse your money putting it in gas tank. You may have a piston ring that is bagged beyond use, if it gets worse. The oil usuage rate isn't terribily disturbing, I have had engines burn more when new and throughout their life then that, and one of those was the best vehicle I ever had. For 11 years it burnt qrt every 3k miles off the showroom floor.

I believe at least one cylinder has been checked with a boro, or a similar camera device. Did those cars you mentioned, did they make the exhaust smell like burnt oil? Im trying to figure out if the exhaust smell i was smelling before the cat was installed back on the exhaust, if the smell was/is caused by the engine oil getting burned or if its something else, like the engine running rich/lean, but, i´ll figure it out, my bet is that the smell comes from the engine oil, that's why i have been thinking if i were to try a heavier oil, at least trough one oil change, if it makes no difference, then i at least know it doesn't matter much what´s the viscosity, the engine burns it anyway, LOL

 

[DGXR]

A daily driver using 1 quart every 6 months? That is not excessive consumption. I don't think you need to change your current 5w40 grade. I wouldn't even bother topping it off as often as you do, just keep a quart or two in the vehicle. For giggles, I would fill it exactly to the full mark and then see how long it takes to reach the low mark. Just once though, because I would prefer to keep an oil burner near the full mark. Also, you might be surprised how long the new cat lives with that little oil consumption.

 

[D1dad]

At the advice of those here I tried slowing down consumption on an 09 altima using 1/2 a quart of 5-30 every 1k (Nissan acceptable btw) with 10-30. Massive fail. The car has never used more. I tried Mobil 1 HM and now PP and it's used more than ever. After I finish wasting money on this I'm gonna go back and waste my money on 5-30 again.