BIG oil leak (okay, not 'massive')

fraigan · Post by **fraigan** » 25 Apr 2010, 13:25

'98 70xc
80k miles
only one [recent] all-synthetic oil change in car's hx

hi all --

so the car has been running a little rough lately (hard to start in the morning, like the fuel pressure isn't holding tight and dropping off overnight) and its getting time for a new oil change. well, low and behold i pull the dip stick and it's low, i look under the car to investigate for leaks and there's oil everywhere.

the oil pan bolts are dripping (but tight), the tranny case is dripping, the drive boots, the rails, everything. about the only place that the engine is dry is the oil filter and everything topside, and everything front side.

i'm pretty sure highway miles at highway speed is responsible for the splatter everywhere but at the moment i haven't any way to clean the engine to monitor the specific location of the leak. so any thoughts as to what the likely culprit could be is what i'm gonna have to work with.

i'm not familiar enough with the engine (but i'm getting there quickly) and i'd only be guessing that it could be an oil sending unit (location ?) or possibly a clogged PCV oil separator (?) like the 850 (if the 70xc has one).

the issue of getting it to start is getting disconcerting as well, but i really want to get this oil mess cleaned up first - literally! (if anyone would like to touch on the hard starts - please, please feel free to mention.)

thoughts? experiences? any assistance is greatly appreciated!

Post by **wheelsup** » 25 Apr 2010, 13:32

Really good chance it's your rear main seal. That is between your engine and transmission, so they have to be separated. Kinda a big job. You can for the time being just keep topping it off. I never let mine get below 1/2 quart low (which equates to halfway between max and min line on dipstick).

Drive your car for a bit then pull the dipstick out. You might see white-ish smoke. Also try driving with your dipstick pulled 1/4" out or so and see if you lose less oil. If you do your PCV system is clogged.

Post by **jblackburn** » 25 Apr 2010, 13:40

Take it through a car wash that has a undercarriage wash (truck wash if there is one close by).

I had oil leaking from a cam seal that blew out that covered everything in oil, and I thought it was the rear main seal.

Once you clean it up, you should (hopefully) have a better idea of where it's coming from. Also, crawl under it and check to see if the turbocharger is covered in oil.

fraigan · Post by **fraigan** » 25 Apr 2010, 13:56

thanks for the quick responses

and thanks for the truck stop idea!

i'm keeping my fingers crossed that it's not the rear main seal - but hadn't thought of the cam seal (hmm... )

the other issue that's come up with both the hard start and the oil mess is that the car (on more occasions than not) indicates a 'warm temp' on the display within seconds of turning the cold engine over. the car doesn't ever overheat, but that immediate warm temperature indicator is making me wonder if it's not all connected somehow (psst.. as well as making me slightly paranoid)

-- b.

Post by **jblackburn** » 25 Apr 2010, 14:19

the other issue that's come up with both the hard start and the oil mess is that the car (on more occasions than not) indicates a 'warm temp' on the display within seconds of turning the cold engine over. the car doesn't ever overheat, but that immediate warm temperature indicator is making me wonder if it's not all connected somehow (psst.. as well as making me slightly paranoid)

Well, it's not connected, but I can tell you that you need to replace the engine coolant temp sensor! That's causing both the rough running and hard start.

Change the thermostat at the same time as well, it's probably bad too.

They're both located in the housing that the upper radiator hose connects to at the left side of your engine. A quick, easy fix...ONCE you get the Torx bolts on the housing out. Get a can of PB Blaster and spray them pre-emptively, and pick up some new housing bolts from the dealer, as you'll likely strip them out.

Is your PCV system clogged? Check out the PCV tutorial pinned at the top of the forum and check your oil dipstick for smoke like in the video there. That's usually why seals blow out in the first place.

fraigan · Post by **fraigan** » 27 Apr 2010, 15:12

yep, i did the dipstick check and it smokes like a french whore (not that i would necessarily know, mind you) - and i haven't yet been able to get to the truck stop to get undercarriage cleaned up. hoping to this weekend. and what an out-STANDing tutorial writeup for the PCV !

btw, thanks for the advice about the temp sensor and thermostat, i'll get on that when i put together a parts list for order. until then , i'll keep topping-off the oil and changing the newspaper in the oil drain pan. looks like i've got my work cut out for me, but it's incredibly gratifying to be able fix issues when i have the support of others who have gone through the same, or similar.

Post by **JRL** » 27 Apr 2010, 16:50

fraigan wrote:yep, i did the dipstick check and it smokes like a french whore (not that i would necessarily know, mind you) - and i haven't yet been able to get to the truck stop to get undercarriage cleaned up. hoping to this weekend. and what an out-STANDing tutorial writeup for the PCV !

btw, thanks for the advice about the temp sensor and thermostat, i'll get on that when i put together a parts list for order. until then , i'll keep topping-off the oil and changing the newspaper in the oil drain pan. looks like i've got my work cut out for me, but it's incredibly gratifying to be able fix issues when i have the support of others who have gone through the same, or similar.

Not necessary to clean it yet, your PCV is 100% clogged
You need to do a complete breather box and take care of anything else necessary THEN clean it up and see what's left that's leaking

Post by **jblackburn** » 27 Apr 2010, 19:32

Not necessary to clean it yet, your PCV is 100% clogged
You need to do a complete breather box and take care of anything else necessary THEN clean it up and see what's left that's leaking

This. Before you do anything else. The pressure has nowhere else to go so it's coming out your seals.

trouty1954 · Post by **trouty1954** » 28 Apr 2010, 12:44

Guys,

Can someone poit me to this PCV tutorial. I need to do mine on my 95 850 T5 and can't see it. Probably just me being thick

Post by **jblackburn** » 28 Apr 2010, 12:46

https://www.matthewsvolvosite.com/forums ... =1&t=28487

It's pinned near the top of the 850 forum in the 2nd block