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TR4/4A Start Up After Rebuild

KVH

Obi Wan
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Well, I haven't got the guts to start it up just yet. I'm worried about everything, including throwing a rod. So, here's my question at this point: Can I let the engine soft idle for a few minutes before I do that hellish- sounding 20 minute break-in at 2500 rpms.
 
The worrier king. Gotta start it sometime. That's why you built it. Yes, you can run it at idle for a while. No ritual is necessary to break in. Do not run it at steady speeds and do not go above 3000 or 3500 Rpm for the first 1000 miles. Less, if possible, during the first 500. I change oil at 250, 500 and 1000 miles.
Bob
 
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KVH,
The break in procedure is designed to make everything fit together after we do the best we can on machining and assembly. The initial start up is a time of great trepidation and expectations and if you do things in the correct order you can rest assured that the process will do exactly what it's susposed to do. All tolerances and torques checked and recorded? Assembly lube and cam lube on everything it should be? Engine turns by hand without any rough or hard spots? Oil pressure is good while spinning the engine with the starter, plugs out? Got spark? Got gas? 3, 2, 1, ignition! Probably won't run very smooth and you'll have to turn it off and adjust the carbs, but that's ok...just record the total time spent at 2000-2500 rpms and fire it up! Monitor the oil pressure and temp and get your 20-25 minutes in.
Next, take it out for a drive, check everything after it gets nice and hot, drive it like you plan to drive...I drive mine like I stole them. Enjoy!
Rut
 
Actually, most cam makers want you to get it to 2000 to 2500 RPM as soon as possible and not let it idle at lower speeds. Their reason (on the pamphlets I have read) is to prevent damage to the max lift point on the cam lobe.
 
Start it, if it has good oil pressure and isn't making any bad noises do the break in, obviously if something doesn't seem right shut it off. Sometimes new motors run pretty hot. If the hood (bonnet) is off, leave it off, a big fan in front of the radiator isn't a bad idea either.
 
Get excited ! Few restoration experiences give as much satisfaction is firing up an engine that you've rebuilt with your own hands ! Does it hold fluids? is the timing correct? am I pumping oil through it? Do I have extra coolant to add while its running? Can I adjust the carbs while its running? Fresh battery? Ventilation? Are the valves adjusted a bit on the loose side if anything? No distractions ? Fire it up !
 
Oil pressure is critical. If it doesn't show good pressure within 30 seconds, shut it down and check it out. I rebuilt an MG TD engine back in the '70s and it fired right up. Use a checklist. If its got spark and gas and they both arrive at about the same time, its got to run. Good luck.
 
If I could do it all over again, I'd use a checklist and record all things done. I'm fairly sure I torqued everything correctly, but it would be nice to see a written record. I'm headed to Chevron for a gas can to partially fill the tank, then vrooom.
 
What a relief. Thanks for all the help around here as usual. It started right up with zero problems and runs great. I did the break in for 25 minutes between 1800 and 2500 rpms, mainly in the 2200 range. I did all this to replace the leaking rear main seal, but the bonus is that I learned my valves were bad, and so a had the head done and rebuilt rest--pistons, rings, bearings, new cam. Anyway, I do see some oil from the rear again (I use the Viton seal), but it's very little so far and I suppose it's just that I didn't do a perfect job. I did try carefully to center it using the supplied tool, but you never know. I had fun, and I'm ready for the next. Love these cars. Happy Thanksgiving to all.
 
It is both tense and rewarding when you start a rebuilt engine for the first time. Congratulations on the startup and Happy Thanksgiving !
 
It is both tense and rewarding when you start a rebuilt engine for the first time. Congratulations on the startup and Happy Thanksgiving !
X2!
 
I missed those so I am a little late. First congrats, one of the most satisfying things in the world of working on cars is the that first start up after you built it yourself.

I have found that the oil leaks you get after a rebuild are often directly related to crankcase pressure, and a good ventilation or pcv set up will alleviate most if not all of it.

It can also self remedy as the rings seat on break in and you get less blow-by into the crankcase.
 
I don't want to jinx myself, but right after those first few drops came out, my floor has been dry as a bone. It's almost scary. No oil anywhere, except for a slight film on the transmission front cover, but not enough that it's dropping off--yet. The pan is dry all around. The rear main seal doesn't appear to be allowing oil into the bell housing. I'll hold off from celebrating until I can report after a nice long drive, but a buddy of mine suggested I use Motorcraft gasket sealant (I think silicone of some sort, gray), and that may have done the job on the pan and front sealing block. We'll see if that slight film on the cover gets worse.

I do have an issue to report. I pulled my choke out on a cool morning here, and Plug No. 1 rather quickly fouled. All OK now after a Carb adjustment, but I don't believe I ever recall a plug fouling like that, and so quickly. It was quite wet, and reeked of gasoline. It did not appear that much, if any, oil was present. Is that sort of an odd occurrence?

PS (I did see a drop of "oily gas" drip off the bottom of the jet housing on the front carb. I guess it's possible that jet got stuck after yanking the choke cable, and really flooded the intake on that side. I'm just not familiar enough with carb issue to say)
 
KVH, Congratulation and happy motoring.
On the plug, you may have gotten a bad one, I've chased many a miss that turned out to be a bad new plug.
Have fun.

Wayne
 
...The pan is dry all around. The rear main seal doesn't appear to be allowing oil into the bell housing. I'll hold off from celebrating until I can report after a nice long drive...

FYI - The club is doing 100 miles to breakfast next Saturday. PM me if you want details.
 
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