went synthetic, now regretting it

[slag]

I normally run walmart special SAE 30 wt in my mf 8 tractor. The engine was replaced about 4 years back which was a year before i got her. I take care of my tractor and it serves me well.

I changed over from sae 30 to synthetic 10w40 this winter and my tractor has never smoked so much. Just idling, it runs fine ,but when you put it under load, its like it has a stuck ring or something and blows smoke like crazy. Doesn't happen all the time, just some of the time.

Ideas? I've never had a lick of engine problems with it before I changed the oil. I'm thinking of going back to regular old SAE 30.

[mark777]

I've heard this before Slag,

Some people are happy and have made the transition to synthetic oil change without a hitch and others have reported the exact findings you've stated.

The way I understand it is IF you use dino oil to break in a new engine and then switch over to full synthetic you will be fine. It's the engines with a few hundred hours or more that don't like the change.

Mark

[Small Fry]

Not that its the problem but how come 10w40 and not 10w30 ?

[butchs_hobby]

I use synthetic oil in every one of my garden tractors, bought everyone of them used so they already had at least 400 hrs on them when I got them. I haven't had a nickles worth of trouble and in fact figure I added to the life of each one by putting in the synthetic oil. My Dad had a MF8 and I put regular 10w-30 in it for winter use and straight 30w for the summer. I suspect you've got carbon build up under the oil rings and the synthetic oil is getting by them under a load. Make sure of the obvious, that you didn't overfill it. If it is carbon build up it might clear it's self up after some hours of use with the synthetic oil. If it doesn't go back to regular oil and quit worrying about it.

[massey man]

maybe it is engine trouble,but if you go back to the regular oil and it stops then you know it was oil.if you do this i sure would like to know what happens.....

[slag]

maybe it is engine trouble,but if you go back to the regular oil and it stops then you know it was oil.if you do this i sure would like to know what happens.....

Drained the oil a bit ago.. it didnt look normal.. it looked watery almost.. it was weird..

I am putting the 30 wt back in now and will test tomorrow.

[Milwaukee]

That not sound good.

I am not expert with this did you not put antifreeze in radiator or it full of straight water? Can you get pictures of that oil on pan that we can see what color that you see is watery.

And did you left tractor outside all time?

[JMC]

I normally run walmart special SAE 30 wt in my mf 8 tractor. The engine was replaced about 4 years back which was a year before i got her. I take care of my tractor and it serves me well.

I changed over from sae 30 to synthetic 10w40 this winter and my tractor has never smoked so much. Just idling, it runs fine ,but when you put it under load, its like it has a stuck ring or something and blows smoke like crazy. Doesn't happen all the time, just some of the time.

Ideas? I've never had a lick of engine problems with it before I changed the oil. I'm thinking of going back to regular old SAE 30.


I suspect the "Walmart Special" low grade oil is what did the engine harm
and not the Synthetic...There is probably wear, wax, varnish etc. combined. The wax and varnish deposits from the cheaper oil did a good job of sealing the wear it caused.

When you put synthetic in there, the superior detergent additives started cleaning up the engine and uncovered "voids" in the sealing surfaces. SAE 30 oil is only good for summer use in very inexpensive summer engines like the all aluminum Briggs stuff they put on box store platforms. In the winter an engine with SAE 30 will run many seconds on startup before any real oiling begins...The SAE 30 is good for sealing up and floating loose parts on cheap and /or tired engines, and does a good job in summer weather. But it's not winter oil.

As others said, sometimes a change over late in the life of an engine is not good, better to stay with what it always had...:goodl:

[butchs_hobby]

The use of a cheap oil is why I think maybe the oil drain back holes under the oil control rings are plugged with carbon. The synthetic oil might clear them out, might not. The MF8 used a cast iron Tecumsch motor and where tough little machines. I repainted Dad's and sold it for more than he paid for it new after he had used it for 25 yrs!

[sixchows]

When you put synthetic in there, the superior detergent additives started cleaning up the engine and uncovered "voids" in the sealing surfaces. SAE 30 oil is only good for summer use in very inexpensive summer engines like the all aluminum Briggs stuff they put on box store platforms. In the winter an engine with SAE 30 will run many seconds on startup before any real oiling begins...The SAE 30 is good for sealing up and floating loose parts on cheap and /or tired engines, and does a good job in summer weather. But it's not winter oil.

As others said, sometimes a change over late in the life of an engine is not good, better to stay with what it always had...:goodl:

Here's some things to consider.......
If your tractor is stored in a heated garage, SAE30 is fine for winter start ups. If its sitting overnight outside or in an unheated garage then 10W-30 should be used.
SAE30 was recommended in the older horizontal cast iron engines for temps above 32*F for Tecumseh and at 40*F and above for Wisconsin. These were not some cheap "box store" engines. Today's aluminum engines like the Kohler Command Pro 22HP on my craftsman use Sae 10W-30.
Also, I'm not sure detergent oils were recommended in those older engines.
Here's what Tecumseh recommended for their HH(Heavy Horizontal) series back around 1970...
http://i2.photobucket.com/albums/y37/sixchows/tecumsehHH120.jpg

[sixchows]

Here's what Wisconsin had to say in the mid-1960's.....
http://i2.photobucket.com/albums/y37/sixchows/tra-10doil.jpg

[sixchows]

http://i2.photobucket.com/albums/y37/sixchows/tra-10doila.jpg

[danbike]

I never believed in synthetic before, but now run all three of our cars, the tractor, and our bikes on synthetic with ONE exception. I use Castrol 15W50 dino oil in the old Triumph. I just don't want to begin getting into a 1967 engine that was designed for dino oil. Somethings just are not meant to be messed with and old British motorcycle engines are one of those things.

[Small Fry]

If you look in to Walmart oil its not really cheap, so I been told. The older guy at Walmart said there oil comes from different companys. He said he never knows what he going to get till he orders it. At that time it shows witch company its coming from. He said for a while its been Exxon Mobil, but it does change. Walmat don't make oil, like napa they just buy who ever is giving them the best price. Exxon moblie and walmart.... Big oil company, big retail, buddys....

Having said that I use Castrol heavy duty 30w in the small engines, mobil 1 in the truck. But the kids want to buy the cheap stuff so I asked about it.

[JMC]

One should always do what the manual says.

Most all the older engines were by and large splash lubed, and had liberal clearances so the oil could find it's way in between parts. Also, the heavier film worked a little better on hills when the splash lubed engines were starving. Thinking was also that contamination in suspension without filtration was a bad thing. It was without a good additive package. Yesterday's thinking.

Oil refiners put the best oil and additive packages in their own brand can, and lesser quality in Walmart's can or any other off brand can. Oil is not oil. They have to meet OEM warranty requirements and uphold their own reputation.

The modern synthetics will work in just about anything, as long as it's not coated inside with varnish, carbon, sludge, etc. The synthetic will then start breaking up this contamination, and uncover voids that were sealed with junk.
Or worse, dislodge sludge and have it jam up oil passages and possibly the oil pickup on pressure lubed engines.

The thing to remember is synthetic oil is superior oil, this is not me talking, it's well tested and documented. It does not ruin engines. It cleans them and lubricates them like no other oil. So if the engine was run with non-detergent oil, all the garbage is stuck to the inside of the engine because it was not kept in suspension in the oil, and removed on maintenance. Once you set it free with a strong cleaner like hot, high detergent synthetic oil, all the problems begin. And so does the misconception that synthetic oil was the demise of the engine.

Use synthetic from the start, your engine will look and run new inside and run strong for a very long time.

Best to stay with what is done on high hour engines. By that point it's too late to worry about anything, just be glad it starts and runs.

[slag]

Just to clarify, the engine in my MF8 wasnt the original. It was a replacement engine, horizontal shaft, pull and electric start, that was a year old when I got the tractor. I've run 30 wt in it and changed it every year. I dont use the tractor much in the summertime, just fire it up to haul my trailer around, move jetskis in the yard, and then mostly in the wintertime to push snow. I keep the tractor in my unheated, but attached garage in the wintertime.

Slag

[Small Fry]

Jmc

I agree with everything you say, but long as you change it, seems like it would be ok. I always use brand name like I said, I could be wrong but I didn't think the walmart oil was Slags problem. Could be I guess.

[DYT4000]

I use Castrol heavy duty 30w in the small engines

It's funny...I was talking to someone just yesterday about all of this. I'll use Castrol HD30 in my old Kohlers that are unpressurized, unfiltered splash lube engines that lasted over 30 years on dino oil. I can live with a rebuild every three decades...

[slag]

started it up tonight and it smelled of burning oil for about 3 minutes.. then cleared right up.. going to drive it around in a few days and put a load on it, but the burning oil smell is gone at least.

[slag]

im starting to wonder if my carb float maybe isnt stuck, allowing fuel to enter the crankcase and thinning the oil.

I'll pull the float bowl off tonight and check.

[DYT4000]

I hate asking stupid questions but I seem to be good at it...you didn't overfill it did you?

[Small Fry]

Does it have a pulse pump ? That might leak gas into the oil if its bad ?

[slag]

Does it have a pulse pump ? That might leak gas into the oil if its bad ?

no pulse pump.. and my float isnt stuck, or my tank would be drained.

[slag]

I hate asking stupid questions but I seem to be good at it...you didn't overfill it did you?

nope, not overfilled.--at least according to the dipstick.

[slag]

nope, not overfilled.--at least according to the dipstick.


I've gone back to straight 30 wt. Smoking is all gone, power is back, starts up easier now as well.

I don't know what to say, other than, whew.. I had to run 30 wt through it, then warm it up, then drain, then put 26 oz of 30wt back in it and its at the bottom of the "safe" level on the dipstick but it runs smoother and better than it has in weeks.