Hello All, I've been away for a long while as it was just too painful (and time consuming with my work schedule being very crazy) to hang out here while I wasn't able to pay attention to my car. My wife is just about done with grad school now and I've decided to dig the project back out of the garage again where I left off.

I have an AR 383 (some of the long timers probably recall some of my story) that is consuming copious amounts of oil (about 2.5 quarts in 500 miles). I'm running a PCV and a breather. I pulled the intake and the runners didn't seem to have any oil residue, or if they did I couldn't tell; looked clean, felt clean. I *finally* got around to doing a leakdown test just today. Let's just say that the Harbor Freight leakdown tester was built on some other planet. After I replaced the secondary gauge I was able to get some reasonable readings. Their percentage gauge scared the crap out of me with readings as high as 43% before the gaugectomy

My readings were (first-second, only took a second on a couple as I was getting tired from taking tons of readings with the first gauge setup in the hot sun and digging out tools I haven't used in a year or more):
1 - 10%-14%
2 - 2%
3 - 8%
4 - 14%-10%
5 - 4%
6 - 6%
7 - 10%
8 - 12%-6%

I had the rockers loose and the intake off, so I just took readers wherever the engine happened to be, which on many ended up at BDC. It had been sitting for about a year without being run, so I sprayed some oil into the cylinders and rotated it over a few times, then went for lunch before taking any readings. . . This engine has 900 miles on it and I have been running Valvoline 5w30. Plugs have been very fouled. I'm guessing the variance in numbers from first to second readings are due to either the gauge sticking a bit (flicking it made a difference, oops, cheap gauges), or possibly due to piston position changing to somewhere more favorable.

Do these numbers look reasonable for an engine with 900 miles? Should I run a single viscosity oil for a while? I think I read somewhere that was recommended for the breakin, but the builder told me 5w30. I don't care at all about going back to the builder, so don't even suggest it, I will be paying someone else to clean up his mistakes (or doing it myself).

Sorry for the long message, but it's been a while!

EDIT: Also, for a little more information, the engine has forged pistons and I did tap some of the valves with a rubber mallet on the high numbered cylinders before recording a number. That helped majorly on one, so it must have had a little crud built up already...

 

TTT

Lars, gkull? Anyone?

 

If those are numbers with oil sprayed in the cylinders, I'd say the numbers are awfully high.

If you remember, we've had horrible luck with AR engines out here: I've torn down 3 AR engines, and every one has been so bad that it's needed a complete rebuild, mostly due to cylinders being out-of-round, out of tolerance, and with taper. You can put some straight 30W oil in it and take the car out and hammer it through 1st & 2nd gear a few times to see if you can get the rings to seat. Then, re-test the lowest cylinders and see if you can hear air blowing out the valve covers during the leakdown. If you have air blowing out the valve covers, your cylinders and rings are bad...

Good luck. I'm re-assembling an AR engine out here right now, too...

 

Whos is AR engines? Just curious...

 

Lars - thanks! Yes, those were with oil, but it wasn't really evenly sprayed, I didn't use a fogger, I just squirted some in as I didn't want to turn it over after the year sitting without a little lube. I then went off for an hour or so before taking those readings. I'm really trying to decide if it is worth putting the intake and all back on again, or if I should just bite the bullet and take it in to a machine shop to have them redo the work. of course it is already overbored .030, so I'm not sure how much more that block would be good for. I know we talked on the phone about issues about two years ago with my first build from AR. This is the replacement for that one, which is why I made the statement about not going back that route again, I'm just tired of it and it's been too long by now anyhow.

ajrothm - AR Racing is a small engine builder in Virginia. Several people a couple years back were buying engines from them with varying degrees of success. Several of us have had some issues with builds from AR. I haven't actually dealt with them in a long while now as I decided to just eat it and make the best of things.

 

These numbers are not real bad at all unless you know where the air is leaking from too! Putting oil in a cylinder can only help seal a ring but not a valve. So I would re-do the the leak down and listen in the intake port for an intake valve leak or the exhaust for an exhaust valve leak. If all is quite in the ports and looking in the radiator also as to no air bubbles then all your leakage is past the rings. You will get a lot of opinions on what is good, but in general an engine with gapless rings will be about 0 to 3 percent and be good. OEM's will veary from 6 to 12 percent by the rings. I know I'm not helping you in the oil use here, but leak down numbers will not tell you about oil use. You have three rings per piston and it only takes one to seal and give you a good reading and still have the other two stuck or broken and you would think all is good!

 

I have always heard that anything over 10% is considered very high. Certainly it would be worth doing again and is no big deal since it is so easy with the rockers off anyhow. It is a little hard to hear exactly where the air is leaking, but certainly I hear a lot of noise in the head area on every one (the valve covers are off as well). I can recheck and listen with a stethoscope to try to narrow it down some, but I would assume the noise I hear in up top like that indicates rings, no?

One other data point that I really should have mentioned, but didn't as I'm not sure what to think about it. . . My fuel economy was *TERRIBLE*. I think I was in the ~5-6MPG range. That of course could have been made that bad by a lot of time tuning and idling and the 2500RPM stall torque converter with the 3.08 rear gears and some spirited driving in hopes of getting the rings seated (and just for kicks) plus a disconnected vacuum advance and a 750DP. Still, I think I had the tune relatively correct on the carburetor and the curve close to a good starting point on the distributor. . . Since it's all apart at the moment, I have a hard time rechecking mileage under more favorable conditions and would need to probably do some more tuning.

Before you ask, the builder did the initial "tune" on the carb, but I think that consisted of taking it out of the box, taking off the choke plate and throwing it out. No choke on a street/strip car? Bah, now I'm getting mad again! I probably shouldn't have asked for a double pumper, but that was my thinking a few years ago... I don't think he touched it otherwise as it had no signs of ever being run that I could tell when I got it. I ended up swapping jets out, but don't recall where I ended up as that was some time back, but I didn't change by too far before the plugs seemed to read reasonably while cruising at 30-35 in first. I think I went down in size IIRC.

EDIT: P.S. I really have no reason to think I'm having any valve sealing issues on a new build. Maybe I'm wrong in that logic, but it seemed unlikely to me that I'd be having anything get past the valves. I could easily give them a coat of oil from above and recheck as well since the intake is off. . .

 

Any comments on my previous comment? I'm hoping to spend a little more time on this over the weekend. I may even be persuaded to put the intake and carb back on. . .

 

I bought my 383 stroker from them about 2 years ago and have had the same problem from day one. Are you sure it's .030 over?? That's what I was told mine would be but this past winter I pulled the pistons out and they are stamped .060 over. I re-honed the cyclinders, put in new chrome moly rings, had the heads rebuilt since just about every valve seal was broken and still the same problem. The spark plugs look great showing no oil problems. The only place I find oil is on the spark plug threads. It kicks _ss but uses oil. I gave up on trying to solve the problem. Sorry to hear others are having the same problem but it is good to know it's not just me. Solution= don't buy from them again.

 

I had 2 AR engines and relatively good luck with them.. However, my first build (a 465 HP 383) was using some oil initially. The oil consumption went away after I installed a crankcase evacuation system. The vacuum created by the exhaust helped the rings to seal..
The plugs on the engine always were a little bit oily but it didn't bother me as the power was excellent.. Drove 15000 miles and about 50 - 60 drag strip passes with that engine and sold it after that and forum member Isoceles (who bought the engine from me) made another 50 passes or so with the engine and put some more street miles on it...
The oil consumption returned without the evacuation system..
My 2nd AR engine was mostly a racing engine and lasted for about 80 drag strip passes. Drove it also for 150 miles on the street.. Never used any oil and the spark plugs were very clean.. Just spun the bearings..
Had the engine rebuilt by a very reputable shop locally and the rebuild also only lasted for about 80 passes before I spun a bearing again... Engines that radical don't seem to last all that long..
The only negative experience with AR was that they did not install the cam that I requested on my 2nd build.. When I did the 2nd rebuild on the 406 myself, I inspected the cam and it turns out that they used a different, cheaper cam than the Comp Cams cam that I requested. Similar specs.. but different.

 

what is a crank case evacuation system? My guess is that cannot be done when using headers?? For awhile I thought possibly the oil was being sucked in the PCV valve because there was no baffle. I installed a baffle but it did not help. It still amazes me that it uses oil but I see nothing on the spark plugs. Just the threads of the spark plugs.

 

It is an alternative to using a PCV and breather. Basically you drill a hole in your headers and run a tube from the headers up to the valve cover. This isn't something one would normally do on a street driven car though. I can't remember all of the details of why you wouldn't want to, but I believe there are some good reasons for not doing so on a street car.

My car is burning enough oil to severely foul the plugs. 2.5+ quarts in 400 miles is not a small amount of burning. You may just not be burning enough to foul your plugs, or they may be hot enough to stay clean?

One other thing is that I know AR tends to use high-volume oil pumps, which may contribute to some oil burning possibly. In my case none of these things seem sufficient though. I also went through and put a baffle on my PCV and those kinds of small simple things. If I can find a good shop, I'll probably be taking the block in and having them check it out and rebuild it for me. I don't care what kind of power I make if I have to clean my spark plugs every fifty miles. My engine also isn't very radical, it supposedly dynoed at 427 HP, which isn't huge for a 383.

-dath

 

Dath, take the motor to a real machine shop and see if they can salvage any parts, one good thing out of this is no one has bought a motor from them ( or at least admitted to it ) for some time now after most if not all of the motors forum members bought were garbage

 

dath
check my site
http://community.webtv.net/MATTGRU/leak

 

MotorHead - Yeah I'm glad that folks picked up on that. I would hate for anyone to have to go through this, our cars can be enough headache at times without the added stress of engine build issues. I'm almost certainly going to be taking things to a machine shop once I have the money and find one I can trust.

Matt - That's good information to have. I'll make sure that once my intake goes back on I check things out well to ensure a good seal if I have further issues. Certainly my leakdown numbers are too high, so I may end up taking the block to a shop before putting it back together.

-dath

 

in 1982 i did a crazy experiment;
cut the ends off oil ring for 0 tension.
it had 180 psi
but used a quart in 50 miles

 

A crankcase evacuation system is basically a hose that goes from your valve cover to your exhaust. The vacuum created in the exhaust creates a vacuum in the crank case and helps the rings to seal. However, this only works with open exhaust.. I ran open exhaust on my '68 on the street and track, so it worked great for me..

 

Well, nastee383 is running a AR engine in his truck and hasn't had any issues with it (as far as I know).. Barkingowl has a AR engine in his wifes car and I haven't heared about any issues that he might have had.. I had relatively good luck with mine except that they didn't give me the cam that I paid for.. It seems like their quality varies a lot but not all of their engines are junk. They do use good parts BUT the inconsistent machine work seems to be the main problem..

 

I`m one of the lucky ones. I`ve put close to 5000 miles on with only one very small issue. Good power, no oil usage, I`m pretty happy overall, but wouldn`t use them again because of all the other problems.

 

If your plugs seem to be dry but still useing oil, this may say that it is the valve stem seals. Generally if the rings are good you have good comprestion and will burn the oil well. (no fouled plugs) What I have seen done alot on small blocks, is that people take the metal shield off the spring and add any type of PC seal and that works sometimes. The metal sheild is part of the valve stem seal by sheilding the seal from oil spayed on it and no kind of seal will work with that happening. Worth some thought anyway. Ih and I have done this repair many times to other engines people have brought me through out the years, so I have seem this work alot.