Recommended oil for an old oil burning engine

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LONESTAR state
I have an 85 mustang gt 5.0 , its low miles, but for being park for month and month without driving, after so many year, I think it damage the valve steam seal... and this year engine was having weak ring from factory. so now it have little blue smoke and its make my oil turn black pretty quick, that tell me its have bad ring. also if I get on it really hard it blow blue smoke. at idle its not bad,but you can tell it have some blue smoke... for now I dont have any trust mechanic that can rebuild this engine the way I like. I know one guy he a very popular mustang restoration , but his shop is 4000 miles away, for now I just want put in some heavy oil to slow the burning a bit for as long as possible, until I find an trust mechanic to rebuild it right. its currently using 10w30 mobil 5000 and FL1A oil filter. I was thinking some shell diesel 15w40 ... thank you every one.
 

OVERKILL

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Pick up an '87 through '89 stock shortblock or long-block (depending on what's available) and put most of the TrickFlow top-end kit on it. Being an '85, I assume it's the 5.0L carb'd GT model? A 650 Holley on a Weiand Xcelerator on those TFS heads, you'll have a seriously woken up car for not much invested IMHO.
 

MetalSlug

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thank for suggest , I know exactly what i need to build this engine to make it the best out off it. will be a 306 when it done. but for now I just need a band aid for this burning oil problem.
 

MetalSlug

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LONESTAR state
I dont drive much to know exactly how much oil it burn, but just say you can see a little tiny blue smoke at idle and first crank and when I push it hard. it have bad ring and bad valve steam seal.
 
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341
Location
Texas
I had a Toyota vehicle years ago with the same problem. For some strange reason or another it wouldn't burn nearly as much Rotella as it would anything else.
 

OVERKILL

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Originally Posted By: MetalSlug
thank for suggest , I know exactly what i need to build this engine to make it the best out off it. will be a 306 when it done. but for now I just need a band aid for this burning oil problem.
IMHO, you'll find that the stock shortblock builds have a better track record than a lot of the aftermarket 306 builds. The HO shortblocks were put together VERY well. I've seen many used in 500+HP builds and have used several myself. They also have the advantage of being massively cheaper while you still end up with forged pistons, hand-ground matched rods...etc. They are a bargain.
 
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77
Location
Washington
Originally Posted By: MetalSlug
I have an 85 mustang gt 5.0 , its low miles, but for being park for month and month without driving, after so many year, I think it damage the valve steam seal... and this year engine was having weak ring from factory.
Can you get to the valve stem seals without pulling the engine? They really aren't that hard to do on most (all?) engines if you can gain access to the valves.
 
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17,298
Location
OH
Try Maxlife 10W-40, an oil that I've used that does what it says it will do in reducing consumption and leaks. Some also report good results with Pennzoil High Mileage. I can tell you from personal experience that Defy won't help, although it's otherwise a good semi-syn at a reasonable price.
 
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2,011
Location
War Eagle
If it is not burning too much and by that I mean more than a quart every 750-1000 miles or so, just keep using the 10w30 you are using. Oil is only $4 a quart or so. I doubt any oil is really going to slow down any burn caused by a ring or rings or seals. Just make sure you check it regularly until you rebuild it. Keep it topped off to full mark and at least you know it has a good oil with good additives in it. Good luck on the future rebuild
 
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1,723
Location
Virginia
Originally Posted By: zrxkawboy
You might try a 10W40 HM oil.
This is what I was thinking. A 10w-40 High Mileage oil wont work miracles, but it might help.
 
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228
Location
NE Oklahoma
You can change the valve stem seals simply by taking off the spark plugs & valve covers, stuffing a little rope into the combustion chamber to hold the valve up, then remove the valve springs one cylinder at a time. You should really drop the oil pan too to clean out the broken bits of valve stem seals down there. If getting it fixed is not an option, first try Mobil 1 15w-50, if it still smokes too much, then use a 2 stroke oil. Your plugs won't foul out as bad and the smoke smells better. Z.
 
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