Restart after rebuild

Good morning,

I am looking at starting my engine for the first time after a complete rebuild. Are there any tips or advice for the procedure and which oil should I use? I cannot find much info on this site but Brian Buckland suggests using Castrol MAGNATEC 10W-40 with no mention of bedding in the engine, while Wilkins suggests a “well known manufacture” for the oil and keeping the engine at 1500 - 1800 rpm for 5 - 10 minutes. I was planning on turning the engine over on the starter with the plugs loose to build up oil pressure first.

Any other suggestions? Should I use a break in oil? Some web sites do not recommend using synthetic oils, at least for the first 1000 miles, because they are too good and the engine will never bed in. I guess when the engine was designed synthetic oils did not even exist, but that does not mean we should not take advantage to them now.

I am in the UK, and I am just starting the engine and hopefully moving the car a few feet. It will be some time before I get to take in on the road.

Thanks in advance.

David

I think any non synthetic oil with a decent amount of zddp additive in it will be fine. I change it after the first 50 miles. Building up pressure before startup can be difficult on these engines but be patient.

David,

Not sure having the plugs loose is a good idea. I would just take them out completely until you build up pressure.

Filling the filter with oil first isn’t a bad idea either.

Good luck.

viewtopic.php?f=39&t=29658&start=

How did you “prime” the oil pump when fitted?
If you used engine oil and it was some time ago during the build, you might find it impossible to get oil pressure by cranking. This is because the oil drains away over time and the clearances of the pump gears often won’t create enough vacuum to pull the oil up from the pan at such low speed.
Starting the engine might do it but I’m guessing you don’t want to do that!
There are a few other ways to overcome the problem if it occurs?

I’m not a believer of anything other than 20W50 of a good quality in our engines. My advice would be to use a good quality mineral oil (I use Valvoline VR1), as you’re not going to rev it highly, for the first 300 miles, then change it.
If you’re going to run it in the “old school” way, then use the same for up to 1000-1500 miles.
After 1500 and you’re happy that the engine is nicely run in, go to a really good mineral oil, like Valvoline), or Millers CSS 20W60 (it used to be 20W50), and that’s semi-synthetic, if you’re going to cane the engine, def use the CSS , road use only, the Valvoline is fine.
I use petroleum jelly in the oil pump for the first start-up after being dry during a rebuild. That brings the pressure up very quickly, (usually within 5 or 6 turns with the plugs out and the oil filter pre-filled), The PJ disperses very quickly and will not harm anything.
Then run the engine for 15 mins at 1500 rpm, especially if you’ve fitted new camshafts, or even just new cam followers. If you have had cams or followers, make sure they’re liberally coated with cam-lube before you start it, especially if the engine has been stood a while before being fitted.

Most over here choose the Shell rotella T6 5-40 after break in

Thanks for all your comments. :slight_smile:

Sorry, Mazzini. I looked but did not find that link.

Cheers.

No worries. Rohan posted this -

I have posted my procedure before but this is what I do to bed in the rings.

Use a specialised running in oil or at least just a standard low cost mineral oil. To good an oil can prevent the rings bedding

Find a quiet stretch of road where you can accelerate with full throttle in third gear from around 3000 rpm to around 5000 rpm

Do a series of repeated full throttle accelerations and cruise down and reaccelerate again in third gear. Do this for about 60 to 80 kilometres or about an hour.The high cylinder pressures from full throttle acceleration rapidly bed in the rings

Drive normally for about 500 km and then replace filter and oil with a good quality synthetic and your done .

When I did my rebuild I used a pressure pot and injected a few litres via the oil pressure line. That said I still could not get any pressure to show just cranking it, however when I started it came up instantly. I used Granville 2050 and changed it after 300 miles to miller’s. Classic 2050

The oil pressure sits pretty constant at 35lbs maybe rising to just under 40lbs

Steve

Yep that’s it guys - Put some hairs on your chest and go straight for the go button!!

This practice of cranking an engine over with spark plugs removed or ignition killed after a rebuild in order to get some oil pressure first is a total and complete waste of time on our type of engines. It could even be damaging if the cranking goes on for an extended period of time. The pump was not designed to supply oil pressure under cranking conditions so it should be no great surprise when it doesn’t. This practice is an old wives tale perpetuated through time and you certainly won’t find it in the factory workshop manual anywhere.

The only circumstances where there may be some merit in prefilling the the oil passageways is if there is a large volume of oil to fill (there isn’t on our type of engines) such as a V8 engine with 16 collapsed hydraulic valve lifters that need to filled before oil pressure can be built up or if the oil system is non standard with long external pipe runs to coolers etc. In these circumstances it would be best to prefill with an external pressure source because like I said the pump is not designed to supply pressure at cranking speeds.

Sorry , I don’t agree with you . I have rebuilt several engine , MG , Triumph , Jaguar , Elan , the last one was my Ferrari V12 250 GT lusso , and I have always prime the oil pressure on the crank ; I have always put a little bit of grease in the pumps before and it always worked with the oil pressure needle jumping quickly . Everytime it was possible , I feeled the oil filters with oil ; unfortunatly , on the Ferrari , they are upside down so …

Guys you really need to open yourselves up to new ways of thinking a bit more. I can’t speak for Ferrari engines (they may have long and tortuous oil routes) but for our simple Ford Kent based engines you are only doing this for psychological reasons (eg. it’s something you’ve always done and accepted in the past) The actual evidence and facts suggest differently.

I’m somehow guessing that there’s not too many people on this forum willing to stand up and support me on this (surprise, surprise!!)

Interesting, 2cams70, good point. I turned another kent engine car over recently without spark plugs and yes, no oil pressure until the I put the plugs back in and started it up. However, I always fill up the filter.

As my engine has never had oil in since rebuild, rather than pouring oil in the filler, I am contemplating removing the cam cover and pouring the oil directly over the cams. At least they will be well lubricated for the crucial first few seconds.

IF your engine has been correctly rebuilt, the engine Assembly Lube will provide adequate protection until oil circulation is established. ‘Running in’ of new camshafts or followers is important.
Turning a newly assembled engine over by hand at least 2 times is a good idea!!

My First assignment out of Uni was in Quality at the Ford Dagenham Engine Plant working with Dover & Kent engines. Had to do things like dis-assemble, measure ,then rebuild & dyno test a Kent Engine. Plenty of Oil splashed about during assembly, then straight to the dyno & fire her up.

After 3 months at Avely I had 4 years in Engine Test at Dunton (Ford of Europe UK HQ.) again, no spin over with no spark before firing them up…

A significant difference might be that sometimes people wait weeks / months / years between rebuilding & firing up their engines?

I made a simple device - after undoing the oilfilter thread adaptor (it came out by accident with the filter) I fitted a standard hydraulic insert thread / tube adaptor, made a little oil tank that could be pressurised ( I used a spare clean eezibleed brake fluid pressure bottle which now is just for oil of course). Then a little air pressure (as the bottle allows) and turning the engine by hand, then by starter, the oil will fill the engine on the intended way, showing oil pressure on the gauge. In my case, I had to check this way as I had no oil pressure reading on a running engine. I found
the needle of the rebuilt dual gauge came loose on postal transport, just enought to slip on the shaft. A second pressure gauge revealed the
erratic readings.
But - a good point - start without pre-cranking oil.
Anna

Clever. :slight_smile:

I’m not a mech eng myself (electronics in my case), but it has always seemed a good idea to get oil pressure before starting a rebuilt engine. Comments above about manufacturers may well be correct, but a production line may have hours or days before an engine is started after building, not the months (or years in my case) for a home rebuild.

There are firms who make a feature of pre-oiling after rebuild:

https://www.ms-motorservice.com/en/technipedia/post/pressure-oil-filling-on-reconditioned-engines/

and firms who sell products to establish oil pressure before each start:

https://www.merlinmotorsport.co.uk/knowledge_base_articles/view/accusump-oil-accumulators-how-do-they-work-281

and formula one teams who establish oil pressure before starting:

https://www.auto123.com/en/racing-news/f1-technique-starting-a-formula-1-engine-part-1?artid=157706

Overall, for the time taken, it seems like a good investment to get oil pressure before firing the engine for the first time.

When I dismantled my engine, It had been 35 years since it last ran, but there was still oil in all the crank bearing, cam bearings and followers. Whilst I expect that having pressure before starting does no harm I expect that none of the manufacturers of our everyday cars pressurises the system before start. None of my everyday cars has had a pressure gauge, ignorance being bliss I just start the engine, the oil light goes out and I drive, the very presence of an oil and temperature gauge provides something to worry about. If I remember correctly from my student days, it is the hydrodynamic pressure generated within the bearing that keeps the metal bits apart, the main purpose of the oil pump is to provide sufficient oil within the bearing for the hydrodynamic process to occur.

Hope this helps,

Richard Hawkins