How often Lubro Molly? - PeachParts Mercedes-Benz Forum

tscorda · #1 08-16-2007, 04:24 PM

I drive about 36 to 40K a year, 90% highway. I put a set of injectors on around 30K ago and treated lubro molly then. Regular filter changes Recently for the past 5k miles noticed much more nailing. Replaced injectors with new and lubro mollyed then changed filters nailing is gone idle is nice.

Is this new diesel with low sulphar causing problems. Maybe I hooked into some bad fuel. What do you recommend to keep carbon deposits low.

Regards Tom

LUVMBDiesels · #2 08-16-2007, 04:29 PM

I do mine every six months or so... around 16k miles for me.

If I were you I would also look into putting some lubricity additives like Lucas fuel treatment into each tank of fuel. The new ULSD does not lubricate enough.

H-townbenzoboy · #3 08-16-2007, 04:56 PM

If you do 90% highway driving, you don't need to do a diesel purge regularly. That in itself will keep the carbon deposits down.

TMAllison · #4 08-16-2007, 05:34 PM

Both of mine have OEM inj's that have never been pulled.

Unless you have a known bad spray pattern or suspect a bad pop pressure there is not much reason to pull them; you certainly should not need to replace them after 30K.

Now, if you been burning alternative fuels, that's another matter.

bgkast · #5 08-16-2007, 06:02 PM

Whenever your wallet is getting too heavy.

Stevo · #6 08-16-2007, 06:12 PM

Not to stir up any old wars but there are some that say "Molly" purging disturbs sediment in the IP which causes trouble", something like that anyway. That might be something too look into, I use it when needed.

bgkast · #7 08-16-2007, 07:09 PM

That's the first I have heard of that. I'm not sure where the sediment would be coming from.

I made my comment because it does not seem to have any (lasting) effect on my cars.

Deni · #8 08-16-2007, 08:42 PM

Just pour a gallon of new vegetable oil with a tank full and you're set. It will lubricate and make your engine way quieter.

tobybul · #9 08-16-2007, 08:45 PM

If you are not already using it, try synthetic oil on the next oil change. I did that on my 84D and theres a noticeable improvement. Its smoother and quieter. Give it a couple hundred miles after the change..... I used Rotella full synthetic 5w40. Mobil 1, Castrol and Vavoline would be good too.

NoSnooz · #10 08-16-2007, 09:28 PM

Quote:

Originally Posted by LUVMBDiesels

I do mine every six months or so... around 16k miles for me.

If I were you I would also look into putting some lubricity additives like Lucas fuel treatment into each tank of fuel. The new ULSD does not lubricate enough.

Would running B20 provide the needed lubricity?

TMAllison · #11 08-16-2007, 09:50 PM

I'm not a petroleum engineer and so may be gainsaid by those that are who hang out here, but from what I have read the ASTM specs for lubrication of ULSD vs LSD did not change appreciably.

If your engine *likes* additives use one, if you notice no difference, don't. My 85 couldn't care less, the 99's idle likes Redline 85 or as little as a 1-2% mix of Bio.

I wouldn't burn unheated SVO or WVO personally as it is known to cause too many inj, IP and ring problems.

If you want to run an alternative fuel and have reasonably good assurance you are not doing harm to your engine, my personal opinion is you should only burn Bio from a reliable commercial pump.

aklim · #12 08-17-2007, 01:39 AM

Quote:

Originally Posted by TMAllison

Unless you have a known bad spray pattern or suspect a bad pop pressure there is not much reason to pull them;

I pulled mine at 120K and one was dirty. They cleaned it for 70 and retested and it passed. 6 tested, 1 failed and was cleaned and retested. I now KNOW that I can go for 120K and then clean them professionally instead of using cans after cans of DP and guess whether the injectors are cleaned. Why go thru all that trouble, I don't understand. Clean it professionally and you KNOW it is good. Otherwise, you spend time hooking up the hoses and maybe disturb a hose or two and get a leak. All so you can take a SWAG as to whether the cleaning job is done or half done. I wish somebody would give me a clear answer on this

dannym · #13 08-17-2007, 08:51 AM

I did the Lubro Moly thing once a long time ago and quickly found out it was a waste of money.

If you really think your injectors are dirty put a quart of tranny fluid in a jar and run that through.

aklim · #14 08-17-2007, 09:31 AM

Quote:

Originally Posted by dannym

If you really think your injectors are dirty put a quart of tranny fluid in a jar and run that through.

Will it hurt the injectors to run on trans fluid? I still think it is better to have them tested. Why does everyone do all these gyrations and pussyfooting around will all sorts of snake oils and what not instead of just taking them to be cleaned?

winmutt · #15 08-17-2007, 10:07 AM

Quote:

Originally Posted by aklim

Will it hurt the injectors to run on trans fluid? I still think it is better to have them tested. Why does everyone do all these gyrations and pussyfooting around will all sorts of snake oils and what not instead of just taking them to be cleaned?

ATF will coke over time. DP is good for an initial car purchase, when you can't afford injector work.