Technical Opinions on engine run stands and engines sitting?

I would like to know what your opinions are on engine run stands vs. running a newly built motor in a car? I've seen some internet opinions that say it's not good for rings and/or bearings to run a fresh motor on a stand with no drag or load on the output as would occur in a car.

Furthermore, what's your opinions on building a fresh motor and having it sit for a while until the car is ready? Does it matter at all, and if it does, what's considered "too long" for a fresh motor to sit? I'm a little skeptical on this as my mechanical knowledge (limited, as it may be) tells me that if the motor is occasionally turned over and properly "primed" before starting/running in the car, that there's little to cause problems. Where am I wrong?

 

A motor can sit indefinitely but to my way of thinking it increases the chance of maybe something (bad) happening to it if it's not bagged up and stored safely. Vermin or rodents setting up shop for example. Fresh or Rebuilt engines need a load put on them right away or asap for the piston rings to achieve a good seat against cylinder bores or they will tend to glaze over. You don't want that.

 

We have been running engines in with no load for 15 minutes to half an hour to break in (flat tappet) cams for decades....never seems to be a problem. The rings will seat just fine.

Storing a fresh engine for a long time (like over a year) is hard on it, because the assembly lube eventually gets gummy, and more importantly, moisture likes to condense inside things. If you can keep the engine from being exposed to daily temperature swings, that will be a big help. Keeping it in an insulated garage or shop is a big help.

Running it on a stand would be great, then you don't have to deal with the transmission, it's easier to spot leaks, etc. I never got around to building a test stand, and I'm not good about keeping my shop neat enough to have room to store one, anyways. But it is a good idea, if you can make it happen.

 

I agree with everything Jim has said above. I think the "rings not seating" situation may have been a problem years ago with chrome rings, but modern rings break in almost immediately. The chance of having to pull a freshly installed engine to repair some unexpected glitch doesn't appeal to me at all.

 

I built a nice engine stand for initial break in of my 392 for the '51. One big benefit for me was a block leak occurred during the initial start up and was easily fixed while motor was on stand. Another reason for the stand was the plan to convert from dual quads to an 8 deuce EFI, faux 97's setup with the motor on the stand. One big mistake was not running the exhaust through mufflers; it was too noisy to think and solve various problems during efi tuning after initial cam break-in. As it turned out, we proceeded to install the motor before the efi was sorted out. and it took about three years to get the fuel injection figured out and running right, so it needed to be in the car.

I think it was very worthwhile doing startup on the stand.

 

If you let a motor sit for quite a while, after being broken in, it would be in your best interest to prime the motor with oil-typically pulling the distributor and spinning the oil pump to get the oil all through the passages before firing. Obviously every motor is different as far as methods of lubrication, however, if the oil slowly seeps to the pan and you go to fire it after sitting for a few months/years, you will run the serious risk of dry starting it and burning up critical components. If you know the motor is going to sit for a prolonged period, pull the plugs and dump some oil in the top end and put the plugs back in. You wouldn't want inadvertent moisture to accumulate through the valves and inside the cylinders/rings. My .02

 

Adding to what Jim said, I have even seen the assembly lube dry up and crystalize .

 

He's not talking about that or, at least I think everybody is on the same page about cam and lifter break-in.

Anyway once that's accomplished everybody also seems agreed don't dink around with it on the stand, excessive no-load idling is not a great idea.

 

When I am storing an engine long term down here in Florida where humidity is a problem. I go to Walmart and get one of the desiccant cans and put it in the plastic storage bags. I change it every 6 months.

 

If the engine is going to set ,It helps save your valve springs ,even if they are stock springs,to loosen them up so you won't have any pressure on the closed springs ,even more important if you run performance springs !

 

I didn't see where he said he planned to go out every week and fire it up and let it idle for a while...????

Then again, I suppose it would be tempting!

 

Great input here, thanks guys. My primary reasoning was being able to check the motors for leaks, adjust carbs, timing, etc. I expect the motor would be in its respective car in a year with any luck. And yes, they're sitting in an insulated garage but sealing them up in bags with desiccant is a smart idea.

 

If the engine is gonna set for any length of time, I would pull the pushrods to keep all the valves seated.

 

"Russ B" gets my award for "Engine Stand of the Year". I thought mine was pretty cool, but that one takes the cake!

 

Look for a thread i started last year. Allot of good info from some knowledgeable hambers, it was called starting an Engine on a stand, or something like that.

Sent from my SM-J727T1 using The H.A.M.B. mobile app

 

My flathead has been sitting for about a year after initial burn in. I make it a point to crank it around every month or so by hand. It will be running again in the next few weeks. I read it somewhere and it sounded like good advice.

 

I built my own, not finished yet. I did add casters.

 

Not true. Springs do not care if they are compressed, as long as the compression does not exceed the point of elastic deformation. They will return to their uncompressed length when the pressure is removed. It is cycles that weakens springs, not compression. At least, as I mentioned above, not compression beyond the point of elastic deformation. Which should not be a problem with valve springs, as the geometry of the valve train should not allow that to occur.

 

??? Is this connected to the concern about valve springs? If so, it's not an issue and would be a real waste of time to do.

 

Sweet!
Can't wait to see it finished....

 

a month will turn into 10 years , plan accordingly

 

If if are asking Allison, no. BlueFlame 6's and I will most likely put mounts for small block Chevy as well.

 

Yep, I've had my 348 for about that long, it was rebuilt when I got it. I thought alot about turning it over by hand, but surely this will just remove any lube. Interesting point about the valve springs, which makes sense. The
'condensation' point does concern me, I have looked in the exhaust ports, and it all looks good in there. I guess i'll find out when I eventually fire it up/seize it?

 

I love my run stand. Saves leaning over the fenders fixing screw ups.

 

I built one to make life easier for running in and changing things. Will need to build a bigger fuel tank one day but it works fine at the moment.

 

Getting mine ready to try out as well. Nothing fancy and less than $30 invested. (casters) The engine stand could get the engine mounts cut off it and become a base for a welding table too however, after the engine is in the car.

My 235 has been built a little over a year....it was well lubed when assembled, but it is just time to prime it up with a drill and get it running. Might light a fire under my ass to get the car drivable!

 

Again, my advice on engine stands is to make sure the casters are big enough (or spaced up enough) so that your cherry-picker and storage stands can roll underneath it.

 

like these---> homemade--->
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Possibly not related to valve springs, but maybe moisture causing rust on the seats/valves and preventing a good seal?