The Diesel Garage banner

93 Mack E7 350 water in oil

22K views 21 replies 8 participants last post by  DmaxEter 
#1 ·
Hope someone can help me here. I have a 93 E7 350 8LL Superliner that I just recently noticed my coolant level way low and checked my oil and it's way up. So I guess a head gasket is my problem here. The truck idles a lot on jobsites and it does have 580K miles but engine was rebuilt at about 525k miles. I bought the truck with 552k, it does not smoke, starts right up in cold weather without plugging it, no power loss.

Do you think it's the head gaskets. A few years ago I had a friend with an older EM6 300hp and I think it was something to do with a oil cooler gasket, not sure, but it did the opposite it filled his radiator with oil.

Any help is greatly appreciated and if it leads to be the head gaskets is this a known problem with the earlier E-7's and how hard of a job with the jacobs on top:thanks:

I have a 1989 E6 350 12sp Superliner and I ran it for 8 straight years and now all it needs is a clutch(thank you my 6 month old driver, keep your foot off it and take off in first not fifth and it would have lasted longer)
 
#3 ·
cracked oil cooler is a possibility but like you said oil likely will make its way into the water as the oil has more psi behind it.

its possible to have HG failure but if it was that bad I would think you could see oil/water leaking around the heads someware???

FJH will know where ya at FRED~~!!!!
 
#4 ·
Thanks guys, I have oil coming down from the top of the head under the jacobs. Jacobs gasket is leaking I have to wash it down good and see if it also leaks at the head gasket. The oil dipstick is about 1 1/2 inches above the max line and I put in a gallon of antifreeze and it's gone and more.

I'm gonna drain all the oil and put in fresh than keep it off. The water seemed to leak into the oil with the engine sitting off for about 2 months oil was fine before it sat. I have all winter to take care of this but I would like to do it myself if possible. Thanks again.
 
#5 ·
Several possibilities come to mind-

Head gasket(s)

cracked head(s)

oil cooler issue

liner o-ring(s) leaking

We have a '95 CH with a E7-350. Over 900k miles, and as far as I can tell, it has never been opened up.
 
#6 ·
bmoeller said:
Several possibilities come to mind-

Head gasket(s)

cracked head(s)

oil cooler issue

liner o-ring(s) leaking

We have a '95 CH with a E7-350. Over 900k miles, and as far as I can tell, it has never been opened up.
Drain the oil pull the pan and preasure test the cooling system!
You likly have leaky liners.
Or as the above post mentioned any of the above!
Most of all don't run it like that!

By the way The E7 Does not have liner Orings!They use silastic or anarobic sealant on the counter bore!
 
#7 ·
Be careful Fred, 93 was the year they changed and went away from the o-rings if memory serves me. I have pulled a few 93's down that had them.

You will have leaking liners causing this problem with out a doubt. The block counterbores will need to be cut most likely. Also, watch out if you do a patch job and only want to repair the one that is leaking. Chances are that it may have flat fire ringed liners and you can not get them any more. if that is the case and you only want to fix the one, you will have to replace all liners under that head to convert to the stepped fire ring grove liners. I wish I had a nickle for every counter bore job I did. Oh wait, they paid me by the hour plus commision so I guess I got more than a nickle for all of them I didLOL
 
#8 ·
DmaxEter said:
Be careful Fred, 93 was the year they changed and went away from the o-rings if memory serves me. I have pulled a few 93's down that had them.

You will have leaking liners causing this problem with out a doubt. The block counterbores will need to be cut most likely. Also, watch out if you do a patch job and only want to repair the one that is leaking. Chances are that it may have flat fire ringed liners and you can not get them any more. if that is the case and you only want to fix the one, you will have to replace all liners under that head to convert to the stepped fire ring grove liners. I wish I had a nickle for every counter bore job I did. Oh wait, they paid me by the hour plus commision so I guess I got more than a nickle for all of them I didLOL
True Pat, I forgot they started out that way!
 
#9 ·
this is starting to look a bit more serious. Where should I start. Should I drain oil and do the coolant pressure test, or is it a guaranteed take apart and work on the heads.
 
#10 ·
Takes an hour or less to pull the pan!Id be doing that first That will let you see where the water is geting in hopfully! don't waste your time changing the oil!No the older engines I have seen the heads crack at the frost plugs between the heads ,the most comon leak externaly there is the hose on the water rail between the two heads.Like Said of its the oring style you may have to have the counter bore re cut and it may mean a tow job to your local Mack dealler hopfully equiped with the tools to do this phone around.
 
#11 ·
I'm somewhat mechanically inclined but I get confused with terms like the counterbore being cut. Does the cutting have to be done to the head or the block? Is there a such cutter on wheels for onsite cutting, or if it is the block that needs cutting, is taking the block out better and taking it to someone who can do the cutting? Is there a kit for this type of overhaul?

I don't have any idea of what kind of money is involved to just taking it in somewhere to get it done but I would like to save some and do it myself since the trucks sit in the winter.
 
#12 ·
The counter bore is a ledge that the cylinder sleeve sits on inside the block. This ledge will get erroded from the engine coolant over time and cause this condidtion. Most of the cases I have seen of this failure were from lack of cooling system maintnence. You have to keep the SCA in check.
There is a speacial tool that is required to cut these ledges. That ledge is also what sets the sleeve protrusion, how much the sleeve sticks out above the blocks deck surface. Since that is the case, the new sleeves will have to be shimmed to compensate for any material that was removed in the process. It is a fairly involved and for sure a precise operation. If a sleeve is set too low, you will be blowing head gaskets on that hole. If one is too high, you will be blowing the head gasket on a hole next to it usually.
There is a rebuild kit you can get from Mack. It is a basic overhaul kit that includes everything except the shims to do this job and then some. I would suggest a complete overhaul since you are going to be that far into it. A compentent shop can do it, but I would only trust a Mack dealer to do it!

As far as cost goes, it depends on what all they do. A basic overhaul wich includes sending the radiator out, sending the pump out, and the overhaul of the engine in my shop will cost anywhere from $13,000 to $16,000. When you get the truck back it will have basically have a new engine.
You may also want to ask about a reman engine while your calling around. It may also be cheaper.
 
#13 ·
Do they ever over cut the counter bores and put the steel rings in place of the softer cast counterbore anymore? I had this done to a couple of Cummins 855’s and a 3304 Cat motor. Haven’t had no leaks on any of those motors since..
 
#14 ·
Lowboy said:
Do they ever over cut the counter bores and put the steel rings in place of the softer cast counterbore anymore? I had this done to a couple of Cummins 855’s and a 3304 Cat motor. Haven’t had no leaks on any of those motors since..
Lowboy
In the case of a cummins / cat the counter bore cracks and falls sum!Their are also cracks that develope between the counter bore and the head bolt holes on the cummins that repair you speak of was developed for those repairs mostly, not saying it cant be done as a precaution in a rebuild but not totaly nessary!
The Mack v8 had this problem from time to time too, the counter bore had to be cut and sleeved as the block as it was didn't have enough material under the liner lip to support and it cracked! the liner and the head clamping down on it put a fair force on that area.
In the case of the e7 the counter bore is half way down the block and the chances of this happening is slim and none The liner is a 1/3 wet 2/3 dri liner and has lots of support beneath it!The E7 engine has some/ alot of good design features And if looked after (DCA) hardly ever fail.Don't get me wrong they have some weaker areas but all in all a dam fine design

Copper as for your situation I would follow the advice of my bud Dmax ,drain the oil change it out pop the rad cap loose (keeps the system from building preasure) and drive it to a dealer.You don't have to do the fuel pump the rad is a good idea have it cleaned They should have the tools and the know how to get ya back running again.With out some specialized tooling the job is not going to be easy in the back yard!The liners take a fair pull to pop em out if you do indeed have the oring style engine you will have NO other choise but to have the block cut or replace the engine .I beleive We stock a short block here at our shop don't know if you got any dealers around your area that do? Check around!!might be a better solution for ya.Or price a remack short block!
 
#15 ·
Thanks all for this help you have posted. I have to say that this truck may have caused a false alarm, for the better.:bow:

The truck sat closer to 4 months actually and I don't recall if I put too much oil in the motor at last oil change, plus it was on a slight incline and all oil had completely drained into the pan over that time. Anyway, I drained the oil and the first gallon or less I put into a small container and found not one water drop:woot:. Well I still drained all the oil and replugged it without refilling and tomorrow I'm going to pull the plug again, before I fill it with fresh oil, just to make sure.

The low coolant may have been caused by leaking from the low coolant sensor plug. There was no trace of a leak when I looked around after it sat but when I looked at the level a few weeks ago and it was low I topped it off and a few days ago I went to check it and there it was a drip drip. I pulled the plug and put teflon on it and refill the coolant a few days ago and tomorrow I'm gonna check it again. Keeping my fingers crossed, it will be a relief.

I'm sorry if any of you feel I wasted your time but you all had some very good info on the subject. Thanks Philip
 
#17 ·
Well, refilled truck with 7 gallons of fresh Rotella 15w40 and new filters. Leak at the sensor plug has been eliminated. Started truck and let it run till water temp reached 160F. checked oil and it was clean like new, didn't turn black right away.

Again thanks to all. So now I have to read up on the other post I have about the 89 clutch. that definately has to be done.
 
#18 ·
Glad you found your leak... you just gotta love the old macks for simple trouble shooting.

Last week I opend the hood of the new granite and my jaw dropped. I could not belive the clutter and lack of space to reach the major engine parts. I laugh sometimes because my 29 year old mack will out run a mid 90s CH and can keep up with the new ones (just not as fastup top).

keep those dogs barkin
 
#20 ·
B422T Mack said:
your not by yourself LMackattack im partail to the ole mechanical Macks myself :Thumbup:


ill take a OLE R OR DM model over a Granite or CH anyday :sly:



Later

Mack

Me too!
My favorite thou is a CL 713 with E7!
You can do an oil change standing up and when your finished warm the engine up crawl in under the hood and curl up and go to sleep by a nice warm turbo and engine block!Althou I can think of better and nicer warm things to sleep by! :) LOL :bow:
 
#21 ·
FJH said:
Me too!
My favorite thou is a CL 713 with E7!
You can do an oil change standing up and when your finished warm the engine up crawl in under the hood and curl up and go to sleep by a nice warm turbo and engine block!Althou I can think of better and nicer warm things to sleep by! :) LOL :bow:
Yeh, my father has a 95 CL713 E7-350 8LL and that oil drain plug is real easy to get to in the front driver's side of pan.

It's OK this last oil change I did on my 93 I installed a FOMOTO valve. Next time I do an oil change I'll open it go change the filters, leave for a couple hours come back close it and refill. This FOMOTO valve is also installed on my PSD, easy to drain. Just gotta make sure oil is hot so it flows nice and don't get stuck in the mud up to the oil pan. Keep the original plug in truck just in case.
 
#22 ·
The easiest by far is the MR garbage truck chassis with a bed that has dump hydraulics on it. Swung an engine by myself in 10 hours one time!!!:Thumbup:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top