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MG TD TF 1500 - Engine Bench Test

Has anyone run their engine before installation in the car? I am considering this to confirm that the oil will stay where it belongs. I am prepared to deal with the fuel supply, no muffler and a kludged up ignition, battery, etc.
The cooling problem is yet to be solved since I have no spare radiator. I am thinking about just connecting the garden hose to the coolant intake pipe and letting the hot coolant just run out the top. Seems sort of crude. Any ideas/experience out there?
Jim Merz

I have no idea how you would connect oil, ignition, etc., but if you turn on an engine for a short time, say a few minutes, you need no cooling. I have done that with an engine in situ and no water, without any problems.

Denis L Baggi


I don't think I would run my engine for a few minutes without coolent. The most I've run is about 15 seconds... probably could go longer, but why risk heat damage on a newly rebuilt engine? Even in cases where a dynomometer is used, the set up requires about 15 minutes of cooling after a high rpm run because there is no air flowing over the radiator. I use a battery with a cut off switch for the starter, a battery charger on a power strip (provides an on-off switch) to power the coil and the fuel pump, and an oil gauge plumbed in. (see image)

Seals can change over time and temperature. I'm not sure how to prove that the lubrication stays where it is supposed to short of driving it.

I've seen engines sitting on their sumps running, but I can imagine that will stress the sump gasket differently than when the engine is sitting on its mounts.


Dave Braun

No problem whatsoever running an engine without cooling for up to about 3 - 4 minutes. The cast iron block has suffient mass to soak any heat quickly away.
Iain MacKintosh

Jim: See no reason why your garden hose would'nt work for cooling the engine.We run inboard boat engines that way on a regular basis.Probably will never come up to temp with an endless supply of cool water but not really an issue for your purposes. As Dave suggests,it might not hurt to knock together a simple stand for the run in rather than letting it bounce around on the sump.
Hang in there
Dan Craig TD/C21793
D.R. Craig

Jim, interesting, I was just looking at a stand on, does not include battery, but has gas tank, temp and tach gauges. You might not want this one, but may give you some ideas.


Larin Mobile Engine Testing Station
Ideal for Testing, Break-In, Leak Detection, Demonstration, Assembly and Detailing

Item # 172601
Shipping & Handling included *
D F Sexton

The machine shop I used had a dynamic tester that spun the crank up to high revs. This allowed them to check compression and check for oil leaks. You might check a local engine shop for this service.
Russ Oakley

Thanks for the inputs, gentlemen. I believe I will buy the Costco stand and connect the garden hose to the branch pipe. I can use it to test both my engines and be satisfied that they are as good as I expect after rebuilding. Then I will have a sligtly used engine test stand to sell. The other ancillary equipment will not pose a big problem. However, I want to locate a piece of large hose to fit the upper thermostat housing so that I can keep my engine dry while testing.
Now to find a short length of that hose.
Jim Merz

We made an engine test stand after fettling the rear oil seal.We found that a 6 thou feeler could be slipped nearly all the way round the scroll before we straightened and adjusted it.
We built the engine up with a flywheel without starter ring so we could see exactly where the oil came from (this flywheel comes of without removing sump)
We found we had a small leak but it only appeared when hot.You dont need a radiator just large drum of water and some hoses.
See the Octagon bulletin June for some silly pics

TF 2884
Ray Lee

sorry june 2006
Ray Lee


I'm more concerned about the head than the block. The head is much smaller mass than the block, and will experience higher temperatures. I think the oil in the sump will stay cool enough for a short time to satisfy the bearings on the crank, cam and lifters, but the differential temperatures between the block and head and the resulting expansion rates make me wonder. That said, I haven't put thermal strips on a head and block and ran without coolent, so I'm only guessing here. I would like to see some data before I went along with your experience, afterall, heads always run hotter than blocks.

I guess what I'm saying is that your experience is valid, and I don't want you to construe this as a criticism, or even a rebuttal to your response because I have no idea if I'm on the right page! I'm just too conservative to try it without testing/exploring the envelope for myself first... but not on my newly rebuilt engine! Your response did make me think, which is one of the really nice thing about this board.

warm regards,
Dave Braun

Dave another thing to consider about starting the engine without really being able to cool it and run for a period of time at different rpms, is the initial break-in of the rings and cam. There are several theories about break-in and I won't start that discussion, but a very short initial run is not one of them.
You might check for oil leaks but not get a good run in on your cam or a seating of the rings.

Just more food for thought-
D C Congleton

Sorry, above message should have been addressed to Jim-

D C Congleton

I bought the Costco engine stand so I won't be doing anything until it arrives in a week or two.
For cooling, I will connect a garden hose to the intake branch pipe and adjust the water flow as seems necessary by monitoring the temperature of the output coolant. As I said in a previous post, I need to find a short length of larger diameter hose to connect to the thermostat housing for the exiting hot water. I want to keep the engine dry.
Another thought is that I wonder if I have to install the generator in order to make the water pump work or will the garden hose pressure take care of that?
Is it harmful to the generator to run it with no electrical load?
The bottom line of all this is that I just don't want to install the engine in the car only to find I have to remove it for some repairs. My current engine in the car is in exactly that shape after only 250 miles.
For initial run-in, I understand that the engine needs to run for about 20 minutes at 2000 to 2500 RPM to break in the reground cam with new lifters.
Needless to say, I really appreciate all your thoughts on this project.
Jim Merz

I must confess, that of all the tool-toys I'd like most to own, it would be a compact engine test stand like what Jim has just bought (see pic). But there are quite a few available - just Google 'engine test stand' and see what comes up.

On the Larin one, how'd you like to be standing at the panel, with a big Chevvy revving at top revs! - see pic!

Gord Clark
Rockburn, Qué.

Gordon A. Clark


"I guess what I'm saying is that your experience is valid"

As I wrote, I did in fact run the engine, reconditioned with new pistons and journals, in the car for a few minutes with no water, and not only there was no sign of overheating, but it ran fine afterwards. So I am not guessing, thinking or pretending, I have done it.

Denis L Baggi

I did check Google with "auto engine test stand" and found nothing in the cost ballpark that I am willing to spend. So, Denis Sextons suggestion was something I could afford and use for just a couple of engines I have.
Does anyone know about using the generator with no load while testing? I'd prefer to have the water pump rotating if that will be necessary but I dont want to damage the generator.
Jim Merz

Jim: Should be no problem with using the generator as an idler. Been thinking about water connections-a trip to the local plumbing department for a selection of PVC reducers clamped into the existing radiator hoses might be an ecomomical way to feed and evacuate your cooling water. Haven't done any measuring for diameters-just thinking out loud.
Dan Craig
D.R. Craig

Congratulations Denis. But I have to ask, what's a few minutes, and at what rpm and load?

My preference is to not, and without real data (time, temperatures, loads, fuel mixture and teardown and examination), I personally won't recommend to someone else that they should.

Dave Braun

I'm not sure what "no sign of overheating' would be without any water in it...? (Ohter then the paint burning off).
Used to run my outboard racing motor out of the water, but just enough to start it (no more then 20 seconds or so)...then drop it back in the water and start it up... Would be leary of anything longer then 20 seconds or so....There again, I don't rev to 5000 either....!
gblawson - TD#27667

'I'm not sure what "no sign of overheating' would be without any water in it...?'

Simple, I look at the water temperature gauge, at the oil temperature gauge, and at the digital thermometer hidden in the glove box which measures radiator and carburettor temperature. I am surprised by that question!

Denis L Baggi


Now I'm really curious. What are temperature are you reading with the water temperature gauge without any water in the system? Are you detecting a temperature rise of the air in the empty header tank? Where is the sensor for your oil temperature located (I don't have one on my car), how does that temperature correlate to the temperature of the block? The digital readout hidden in the glove box is using what type of temperature sensor, a pair of simple thermistors, or something more sophisticated? Where are those sensors located, are they measuring carburetor inlet air temperature and radiator coolent temperature? Absent water in the radiator, what is the radiator digital thermometer measuring?

Sorry for the surprising questions, but I think both Gordon and myself are wondering how all those temperatures help you in running an engine without coolant for testing purposes.

Dave Braun

Dave, let me try to answer you. First, as I wrote, I ran the engine that way for only a few minutes. The temperature gauge for the water is at the back of the head, so I gather I am reading the temperature of block and head. The sensor for the oil is located inside the sump, so there is no problem reading that. The digital sensors are located: one on the radiator - so with no water I don't know what it is reading - and the other two at the sides of the carburettor bowls - I used that to prove that the temperature at the front carburettor is higher than that at the back, courtesy of the fan. The electronic sensors are called KTY100, they look like black plastic transistors with the middle lead cut out. The device was a from a kit, if you want more info I may find it on the web.

I do not know exactly what you measure with no water nor coolant, the important thing was not have it become hot, e.g. by watching the oil temperature, and that worked. But I would not claim it works for more than say five minutes, I was careful.

At your disposal for any further questions.

Denis L Baggi


When Rob Medynski was operating MGTs (NJ), he had the front half of a TD chassis mounted on casters, as a test stand. No need to find accessories, as your extra bits would mount right on. Had the firewall stuff, with gauges, etc.

Paul Gaynor

if you are just wanting to know if the oil is going to stay where it belongs wouldn't it be easier to just use a pressure pot with 5 quarts of oil, charged to 0 psi and connect at a galley plug? this fills the oil pan, checks for leaks and pre-oils for the start. regards, tom
tm peterson

I have the front half of a TD chassis and a slightly butchered complete one, either would work as a test stand. If anyone is interested they are free but need to be picked up or shipping arranged.
Hugh Pite
Hugh Pite

Jim. if you're worried about cooling, just plug up the water outlet and fill the block with water, that will take cae of any hot spots and you can dip your human temp guage in the top hole to check for overheating! Don't worry about connecting the belt. Regards, Richard.
R Payne

This thread was discussed between 16/08/2007 and 03/09/2007

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