Cream puff Engine, in a dilema?

Fatboy 18

Enthusiast
Joined
Jan 16, 2008
Posts
5,092
Reaction score
3
Location
Surrey, United Kingdom
OK need some advice from you guys that have rebuilt engines.

First off I am no engineer, I can pull things apart and have in the past replaced Timing cover gaskets, Half shafts, UJ's, Engine mounts etc. But Have not ever pulled the heads on an 8ltr V10 engine or taken out pistons.

If I were state side I would have no problem taking it to a Vendor here, but being in the UK apart from Viper Baz UK, there are very few people I (if any) I would trust to work on my engine.

Car has now done just over 66K and when I check the oil it always gets dirty very quickly. When I change the oil I always drop the pan and clean that out too so there is hardly any old oil left in the engine to contaminate the new oil.

I do have a tendency to keep the engine on cam (it sounds better with a fully de-catted exhaust) and I do not ever really drive the car sedately (its a weekend toy race car and I use it as such).

Here's things that I have noticed.
1/ I do not have a catch can set up. I did buy a can but Trying to work out how to plum the thing I found really complicated and so its sitting on the garage shelve and I've not really had enough time to work it out :(

2/ I have noticed the throttle body butterfly's have a film of oil on them, so there is evidence of the car sucking oil into the engine.

3/ I have purchased a set of Valve guide oil seals, but if i'm honest I am not confident about fitting these so these are also sitting on the shelve.

4/ Car is using oil, I guess about at least 1QT every 1000 miles. If the cars engine is running at tick over you do not see any blue smoke out the rear of the car, but sometimes if I put the pedal to the floor when driving you sometimes get a little bit of light blue smoke, but not always.

5/ I do enjoy going down through the gears and letting the engine perform the braking, so I guess I am drawing oil up from the crankcase which may be getting past the rings and therefore is the likely cause of my problem?

I have tried to do a leak down test and compression test but this is very hard with one person and have got non conclusive results :(

Don't get me wrong, the engine still pulls like a train and the car is a blast to drive but I think the writing is on the wall for some engine work.

I also have a set of Bellanger headers to fit, but I do not want to fit these if I have to pull the heads off the engine as its more expense on gaskets etc.

I have also purchased from a UK Viper member a set of Diamond forged pistons and Total seal rings, which are also sitting on the garage shelve for a rainy day.

I do not have any big end shells or con rods, bolts etc.


So where would you start? The last thing I want is for the engine to get damaged.
 

DrumrBoy

Enthusiast
Joined
Jul 21, 2003
Posts
2,612
Reaction score
0
Location
GA
FB, as you point out it seems likely that you're dragging some oil through the intake which is one cause of oil consumption. Not a bad one, and one that can be fixed by doing the catch can. It makes a huge difference if you're driving the car hard. I found that side-to-side g forces fill up the can far less rapidly than heavy braking does. On track, I fill mine up every 40 minutes or so....I drain 6-7 ounces of nasty oil-froth out of there twice a day under track use conditions. Do try to get that thing plumbed up, it'll make a difference.Also as you state, a leakdown will tell you if you're pushing oil past the rings (and losing compression). If you don't have the meters, can you have someone do that for you? You may have a cylinder or two that just don't hold the pressure......not the end of the world but would be good to know.
 

JoelW

Enthusiast
Joined
Mar 30, 2010
Posts
452
Reaction score
0
Location
In a Tennessee hollow!
You need to start with a cylinder leak down test as you have stated. Buy a friend a pint and get some help. I assume you have already checked the compression but if not do that first - dry and wet (a few squirts of oil in each cylinder). Depending on what you find, then you can proceed to the leakdown. If you start with cylinder #1, you can follow the firing order and check each cylinder for leakdown - just be sure each is on TDC. Chances are, after a few cylinders, you will find that you have a standard leakdown - especially since you said the engine runs well. With the mileage you have, you should get somewhere around 92% but that could be off. Anything over 90% would be pretty good - especially if the engine is cold. Pay attention to where the air is coming out. You can put paper over the oil filler area to detect pressure there and hear it in the intake or exhaust - even with the long exhaust on Vipers. My guess is that you have valve guide seals that are letting oil by the valves or worn guides if your compression checks out well. If your rings were really worn, you'd notice smoke on acceleration. Valve guides and seals usually pull oil past on deceleration - but you may notice oil burning after deceleration and then when you accelerate you see the smoke. Depending on what you find, you can remove the valve covers and check the seals. If you are very careful, you can put new seals on without taking the heads off using air pressure to hold the valves closed. Just buy the tool and use lots of rags to avoid dropping the retainer clips into the engine!!! An alternate involves nylon rope but that's an old trick. Either way, you can do this. But is sounds like you are ready for a rebuild with the parts you have so you just need to find a good machine shop.
 

Ryan_DSA

Enthusiast
Joined
Jun 20, 2012
Posts
45
Reaction score
0
Location
Wisconsin
having no cats, you could get a bit of black smoke on shifts and letting off throttle. im not 100% sure but a tool for doing LS valve springs, could be used with the heads on car, comp cams makes it, i ll try to get my hands on one and try it on a viper head.
 
OP
OP
F

Fatboy 18

Enthusiast
Joined
Jan 16, 2008
Posts
5,092
Reaction score
3
Location
Surrey, United Kingdom
Many thanks for the input guys,

should the compression tests and leak down tests be done with the engine hot or cold?

The reason I ask is just how hot should the engine be? What I mean is, if you bring the engine up to normal operating temperature, If you were to start at the first cylinder performing a compression test after switching off the engine, by the time you got to cylinder 10 surely there would be a big heat difference or am I being too critical?


Should I wait to see if I won 2nd prize in the raffle for the Gen2 twin turbo kit? :D
 

klamathpro

Viper Owner
Joined
Oct 7, 2005
Posts
925
Reaction score
0
Location
Detroit
Another thing to try, especially if you ever track the car, but even if you don't.... 15w/50 Mobile 1. Now before you say NO WAY, hear me out. This came straight from the guy who helped design your engine, Dick Winkles. Dick said it's perfectly safe to run 15W/50 all season long (warmer months) but especially for track events. I decided last summer to run the stuff in my RT/10 because I was having low oil pressure issues on hot track days. Well, not only did it cure the low pressure issues, it made the car run stronger. My 94' RT/10 has countless times proved to be faster 0-80mph and on from a roll than my GTS, even when swapping drivers. My theory is the thicker oil seals everything a bit better such as valve stem seals, especially at higher temps, and hence the stronger results. It can help prevent valve stem blow-by as well. I don't know what it does for sure, but I'm never going back. The only side effect was a barely, slightly louder lifter tick at idle.

The heavier oil may help with your oil consumption aside from also needing a catch can or new PCV valve. What do you have to lose if you will one day rebuild anyways?
 
OP
OP
F

Fatboy 18

Enthusiast
Joined
Jan 16, 2008
Posts
5,092
Reaction score
3
Location
Surrey, United Kingdom
Wow, thanks for that. You may be onto something there, I find it hard to get Mobil 1, 10/30 here in the UK so I run Mobil 1, 0-40 This may be too thin?
 
Last edited:

ViperTony

Enthusiast
Joined
Apr 3, 2006
Posts
7,554
Reaction score
0
You may also be coughing oil through the CCV (crankcase valve) that runs from the top of your engine block and tee's into the intake manifold. For me that was the definitive source of oil in my intake. (http://forums.viperclub.org/threads/641305-My-GenII-CCV-Air-Oil-Seperator) http://forums.viperclub.org/threads/647316-DIY-Breather-System-from-AC-Performance

It's not that the CCV orifice is bad (it's just a fitting, no valve) but the crankcase will puke through that and directly into your intake. With my catch can setup for CCV, it's catching oil mostly during track days and during very spirited driving.

I have two catch cans, one for the CCV and a separate one for the valve covers. I catch nothing from the valve covers.
 

REDSLED

Enthusiast
Joined
Jan 30, 2002
Posts
1,484
Reaction score
0
Location
Bakersfield, CA USA
5/ letting the engine perform the braking,
Install the oil puke cans. Could be rings. Once you get this sorted out, let the brakes slow the car, not the engine. You are putting unnecessary stress on the drive train that doesn't need to happen. I drove your car to the max on the track for several sessions before you purchased it and the stock brakes slowed the car down just fine. If you are tracking the car best to use 15/50 Mobil one or the equivalent. Been running that on my race rig for years and no issues. Best of luck :)Cheers,Jonathan
 
OP
OP
F

Fatboy 18

Enthusiast
Joined
Jan 16, 2008
Posts
5,092
Reaction score
3
Location
Surrey, United Kingdom
Many thanks Redsled, great to know you had a blast driving it :2tu:

Thing is when you let the engine do some of the braking, the note from the exhaust pipes is EPIC! :dance:
 
Top