Priming a newly rebuilt engine

jms

jms

VIP MEMBER
Joined
Jul 26, 2005
Messages
389
Country flag
So yes I forgot to prime everything with oil and now I'm at a point where I actually want to start the engine for the first time. I've probably kicked the engine over at least 100 times and still no return oil out of the vertical pipe with a small hole inside the oil tank of my Atlas. Will this approach ever produce enough pressure to show return oil? I can feel and hear air being pumped out of the pool tank. Thanks
 
jms said:
So yes I forgot to prime everything with oil and now I'm at a point where I actually want to start the engine for the first time. I've probably kicked the engine over at pumped out of the pool tank. Thanks
Click to expand...
It SHOULD...usually they do. Oil filters take an incredible amount of time to fill. I usually try to prime a fresh engine with a bottle of oil hanging above and connected to the rocker oil connector on the cam cover. Fills the crank and pump.
 
New rebuild takes a while. You sure you've actually kicked it over with the plugs out 100 times?

Kicking is not like the engine running. If you put your finger on the top of the return tube it should show wet with oil. And you might see some evidence of oil disturbance on the surface of the oil in the tank close to the return pipe.

If you have actually kicked it over 100 times, take the exhaust valve covers off and squirt some oil into the exhaust side down the pushrod tunnels, then start it after putting the valve covers back on. If only 50 times, kick it over another 30, and then start it. The oil should burble out of the return unless you... well screwed something up. If you want do another check before firing it up and make a little mess, you can remove one of the rocker spindle covers. Oil will dribble out if it is getting to the rocker spindles.

When I was a kid in my 20's I used to just start the engine. The internet full of forum doom and gloom experts did not exist to keep me worried about everything I touch. lol
 
Last edited:
jms said:
So yes I forgot to prime everything with oil and now I'm at a point where I actually want to start the engine for thill rete first time. I've probably kicked the engine over at least 100 times and still no return oil out of the vertical pipe with a small hole inside the oil tank of my Atlas. Will this approach ever produce enough pressure to show return oil? I can feel and hear air being pumped out of the pool tank. Thanks
Click to expand...
If you built it with assembly lube and didn;t make either of the mistakes below, just start it up. Next time, fill the oil filter before putting it on. You've kicked it 100 times more than I would but I do that the oil in the tank a day or two before starting and I do have a squirt of oil over each valve sprint to be sure the timing chest and tappets/cam have some oil. The oil only dribbles out of the return on a Commando so you might just be missing it. If there's no oil in the sump then there no oil to return. Assuming no mistakes the oil will return without two minutes, if the oil filter is fully, then within one minute.

The two biggest mistakes I've seen are:
1) The oil pump gasket on backwards - crank and rockers get oil but no oil return. No big deal if you have a crankcase breather that returns to the tank.
2) The rubber seal between the oil pump and timing cover missing - engine will be destroyed.

If you're confident of those, start it up. If not, take the timing cover and oil pump off and check.

If nothing is lubed, kicking it will do basically the same damage as starting it!

What is a "pool tank"?
 
Take the plugs out, ignition off, push it around in second gear, till you get oil pressure, then start it, I don't think you'll get damage without compression.
 
Last edited:
marshg246 said:
If you built it with assembly lube and didn;t make either of the mistakes below, just start it up. Next time, fill the oil filter before putting it on. You've kicked it 100 times more than I would but I do that the oil in the tank a day or two before starting and I do have a squirt of oil over each valve sprint to be sure the timing chest and tappets/cam have some oil. The oil only dribbles out of the return on a Commando so you might just be missing it. If there's no oil in the sump then there no oil to return. Assuming no mistakes the oil will return without two minutes, if the oil filter is fully, then within one minute.

The two biggest mistakes I've seen are:
1) The oil pump gasket on backwards - crank and rockers get oil but no oil return. No big deal if you have a crankcase breather that returns to the tank.
2) The rubber seal between the oil pump and timing cover missing - engine will be destroyed.

If you're confident of those, start it up. If not, take the timing cover and oil pump off and check.

If nothing is lubed, kicking it will do basically the same damage as starting it!

What is a "pool tank"?
Click to expand...
Thanks Gregg. That was a typo. Should have said oil tank
 
Schwany said:
New rebuild takes a while. You sure you've actually kicked it over with the plugs out 100 times?

Kicking is not like the engine running. If you put your finger on the top of the return tube it should show wet with oil. And you might see some evidence of oil disturbance on the surface of the oil in the tank close to the return pipe.

If you have actually kicked it over 100 times, take the exhaust valve covers off and squirt some oil into the exhaust side down the pushrod tunnels, then start it after putting the valve covers back on. If only 50 times, kick it over another 30, and then start it. The oil should burble out of the return unless you... well screwed something up. If you want do another check before firing it up and make a little mess, you can remove one of the rocker spindle covers. Oil will dribble out if it is getting to the rocker spindles.

When I was a kid in my 20's I used to just start the engine. The internet full of forum doom and gloom experts did not exist to keep me worried about everything I touch. lol
Click to expand...
That’s funny you say that because when I was in my 30’s I would just start it after a rebuild as well without a care in world! 😜
 
jms said:
Thanks Gregg. That was a typo. Should have said oil tank
Click to expand...
So after a lot of kicking looks like oil made it to the sump and the head, which I assume means the crank filled. Some oil ( not much) is evident having exited from the small hole in the vertical return pipe inside the oil tank
 
jms said:
So after a lot of kicking looks like oil made it to the sump and the head, which I assume means the crank filled. Some oil ( not much) is evident having exited from the small hole in the vertical return pipe inside the oil tank
Click to expand...
Fire it up.
 
Ignorance being bliss, after my complete rebuild of my N15CS, I sprayed starting fluid onto the single Mukuni's foam filter and started kicking that beast. My knee and achilles can only take so much, especially on a tight, newly rebuilt engine. I used that red assembly lube; I'm not a complete ignoramus, only partial. It snorted and popped on 5 or 10 kicks, then fired up & ran. I saw oil at the tank return and rode off. Not a hiccup engine-wise now after 1,500 fun miles. Don't forget to post a video.

Mine after 2 years on/off rebuild then 5 mins thrashing it to life:

 
gpzkat said:
Ignorance being bliss, after my complete rebuild of my N15CS, I sprayed starting fluid onto the single Mukuni's foam filter and started kicking that beast. My knee and achilles can only take so much, especially on a tight, newly rebuilt engine. I used that red assembly lube; I'm not a complete ignoramus, only partial. It snorted and popped on 5 or 10 kicks, then fired up & ran. I saw oil at the tank return and rode off. Not a hiccup engine-wise now after 1,500 fun miles. Don't forget to post a video.

Mine after 2 years on/off rebuild then 5 mins thrashing it to life:
Click to expand...
Permatex Ultra Slick assembly lube saves the day.

I have not done a YouTube video. I am not real and may be a bot.

Are you using a phone to create the videos?
 
Schwany said:
Permatex Ultra Slick assembly lube saves the day.

I have not done a YouTube video. I am not real and may be a bot.

Are you using a phone to create the videos?
Click to expand...
Permatex, yes, on everything internal. I also have some moly stuff but the Permaex was satisfyingly clingy.

Yeah that's just a phone for the YouTubes. One of these days, I'm gonna snap a riding video using my obsolete Rylo 360 cam I bought, which failed miserably as a commercial product, but still works. Takes a lot of horsing around to get it posted but looks quite good once done.

Anyway my knee and/or ankle would need a lot of rehab if I kicked 100 times. And I've always had great knees and ankles, played hockey for 20 years no injury.
 
concours said:
OP, did you fill the crankshaft with oil before putting the timing cover on?
Click to expand...
I was going to mention everything that should be done, but it sounded like it was too late and the kicking had already started.

If assembly lube was put on everything it might survive without issues if the crank started filling rapidly. Otherwise the big end shells and journals will have about 15 years of wear on them in 10 minutes or less.

Anywho, if it runs and does not sound like a bucket with 2 1lb lead fishing weights in it, I'd change oil in 50 miles and see what it looks like.
 
I worked on an assembly line for the A series Mini engine for a couple of weeks back in the 80's, no assembly lube was used. At the end of the line 1 in 10 engines were taken off to hot test and supplied fuel oil and water for 15 mins, rest went had oil put in the sump and then sent up to the car assembly plant and got started at the last station before the end to be driven 20 yards for a rolling test. I assemble the bores dry, use assembly lube on the bearings, cams etc and start the engine dry so those rings get bedded in quickly as in a few seconds the oil arrives. When we got Honda engines in from Japan they were 100% not hot tested and we had to add the oil to the sump, lot less failures, its was 50 in one year at production rate of 2000 a week, the previous in house engines failure rate was 80 a week.
 
I had an Austin Mini with a 998 in it. Before the 80's existed though. I never rebuilt that engine, and have no clue what the labor was doing on the assembly line.

Excuse yet another excursion off track. :)
 

Similar threads

R
  • Locked
1st Start on rebuilt engine.
2
Replies
33
Views
4,476
Scout63
S
DonOR
  • Locked
Newly Rebuilt Motor Wont Start. 10 common faults?
2
Replies
31
Views
4,109
Steves
Steves
D
Pre-unit T110 priming a rebuilt engine
Replies
10
Views
2,496
grandpaul
grandpaul
N
  • Locked
Tuff to Kick - Rebuilt engine
Replies
10
Views
1,181
frankdamp
F
M
  • Locked
Oil Pressure @ rebuilt engine
2 3 4
Replies
62
Views
5,600
kraakevik
K
Back
Top