I just wanted to post an update on my progress. Last evening, my neighbors and I started my 390 V8 for the first time (engine specs are listed below). I had a small fuel leak that we fixed, but the engine fired up after adjusting the distributor a bit. We ran the engine for 30 at/or above 2000 rpms to break in the cam. During this 30 minute period, I had two major concerns.

First, I was concerned about the temperature. The temperature gauge climbed steadily to 220 degree and stayed there. I am using a large 4 row copper/brass radiator with a flexfan attached to the water pump snout (no fan shroud). Is this temperature typical during initial start-up? We thought that the new thermostat might have malfunctioned so, I pulled the thermostat (195 degree) today and boiled it in water to make sure it opened correctly. Everything checked out ok. What could cause this high temperature?

My second concern was the oil pressure. I am running Rotella 10W30 oil with a Redline additive (ZDPP). Further, I have a high volume Melling oil pump. When the engine was at/or above 2000, my oil pressure gauge showed 25 psi. My neighbors, thought this was way too low. After doing some research within this forum, I found that the only spec provided by ford was 35 psi at 2000 rpm. Should I be concerned? If so, what are my options?

Finally, I am using new Ford Motorsport electric gauges manufactured by AutoMeter. Your thoughts and inputs are appreciated.
<O
Lance


Block: 390 bored .030 over
Heads: 410 heads (C3AE – 6090C; new seats, valves, and guides)
Pistons: TRW pistons (.030 over) L2291Fspistons to be below deck was .012".
Cam: Speedpro
Intake Exhaust.050 Dur. 214 224
SAE Dur. 292 302
Cam Lift .295 .310
Valve Lift .510 .536
Lobe Ctrs 107 117
Lash HydRods:

stockCrank:
stockHeadgasket: standard gasket that came in SpeedPro kit Intake:
Edelbrock Performer (gasket matched)
Carb: 600 cfm edelbrock with electric choke (non emission)
Distributor: D.U.I
Headers: Sanderson

 

Great job on getting the machine running again!!!! I am not sure about the oil pressure but the temperature seems a little high. I would blame it on the flex fan with no shroud. While the flex fan will pull alot of air at higher rpm's, at 2000 it is not functioning completely. I am running a stock fan with the stock shroud on my rebuilt 390 and it runs at 190-200 and goes down at 200 back to 190( 195 thermostat).

 

**** almost forgot to say "CONRATULATIONS!!!"

The high temp is normal as the rings/bored make friends again. It should have leveled off later in the 30 min if you let it idle after that. I ran mine for about 10 min revolving the rpms between 1500/2500 about every 15 sec and then it began to warm to about 200º Then I let it run in 1 min intervals climbing and descending from 1500/2500 in 500rpm increments. Then finally let it idle as the temp fell back to 195º from a max of around 215º but it never spewed any goo. I'd check the timing next time around to be sure it's in decent position. And try to get the air/fuel setup with a vac gauge asap.

As to the oil pressure, how did the rocker assemblies check out ? Does the crank have main journal grooves ? Mine runs about 32-35 on the OEM gauge and about 45-52 on the Autometer @ idle (all the engine's oil tolerances were text book)

 

Jsbiohazard, that you for making me think. It makes perfect sense that one of the major contributing factors to the high temp was the flex fan. After reading and reflecting upon your comment, it finally sunk in that a flex fan doesn’t operate at its full potential when a vehicle is sitting and running at 2000+/- rpms. A flex fan is designed to flatten out as rpms go up, as the vehicle should be taking on more airflow when moving forward. The second major contributing factor, as Redmanbob suggested, is the rings meshing with the cylinder walls. This weekend I hope to start the engine again using a water hose in the radiator as suggested by Steve Christ to keep the engine cool. During this run, I hope to dial in the air/fuel setup.

Redmanbob, I believe the rocker assemblies checked out fine. They are non adjustables and have been torqued to spec as Steve Christ suggests. Further, I heard no rattling from the upper end during start up or breakin.

I am unsure if the main journals have grooves as the machine work and assembly was completed several years ago by a mechanic and I don’t have a spec sheet. I was hoping that the oil pressure during break-in would be around 50 psi and drop to 25 psi upon idle, but that was definitely not the case. The oil pressure never got over 25 psi. Doing a search on “low oil pressure” here within the forum, I found many sources to low oil pressure and am unsure on where to begin diagnosis.
<O
Before I start up the engine again this weekend, I plan on changing the oil to a heavier weight (VR1 20W50 – FL1A oil filter). I don’t know if this will help, but I am hopeful.

 

I wouldnt bother with the oil just yet IMO. As an R&D Supervisor one thing I learned is change things 1 variable at a time if you want to get to the bottom of things.
The engine was assembled 2 years ago and sat fresh until now ? Thats a little hair raising, this may be your temp issue in a nut shell. Fresh bores that sat for two years would surely have (lightly)rusted walls and possibly rings. Myself, it would have come apart for inspection first. BTJM
I think the old gal just needs time to get past the honeymoon and used to the laundry & chores

 

Did you try a different oil pressure gauge? We started mine a few weeks ago and it's hovering around 70 using a mechanical gauge. 25 sounds a little low for a fresh rebuild IMO.

 

An even bigger concern than the flex fan (I ran one for years and never had any overheating) is that you have no shroud.

Without the shroud, if you are running the fan with the same spacers that were stock WITH the shroud, the fan will be too far away from the radiator to pull air through it.

Either get a shroud or move the fan closer to the radiator - I forget what is recommended - guys?

--

Oil pressure is pretty low, you're right. But 10w30 is kinda thin. I'd see what 10w40 does before getting nuts about whether or not it's OK.

However, I'd make sure the bypass valve in the pump isn't stuck open - which it might be if there's some metal from the rebuild floating around.

When it's cold and you start it up, what's the pressure?

And definitely make sure you have the right sender for that gauge set

 

Guys,

Thanks for the replies. I have ordered a radiator shroud and it should be here in a couple of days. Krewat, you are exactly right when you mention the distance between the fan and radiator as there is 4” between the fan and radiator with a 2” spacer. I am definitely interested in seeing the fan moved closer.

Redmanbob, thank you for the R & D suggestion (taking one variable at a time). I am going to get a mechanical gauge so I can check oil pressure. If the oil pressure stays the same, I will change the oil to a heavier weight; 10W40.

Krewat, I am unsure how to check the bypass valve in the oil pump. If you provide me directions, I will do my best to follow them.

Thanks for everyone’s input.

Lance

 

About the only way is to remove the oil pump Sorry...

Do all the other stuff first, then if the pressure doesn't come up the way it's supposed to, I'd talk to the machinist(s) who did the work.

 

You really need to use a WAY heavier weight in these old tanks. I use 20w50 and thats the only way i can get anykind of oil pressure. I think everyone here is spot one with the fan though. 390s are notorious for running low oil pressure and high temps. I took the thermostat out of mine altogether and it runs real low. I would use heavier wieght oil first. In the summer I've been know to run straight up John Deer 40w in mine.

 

I apologize for the delay, but it has taken me awhile to obtain the suggested parts. To bring you up-to-date, I purchased a 4” fan spacer (from a local salvage yard; 1974 F100) which brought the flex fan within 1 ½ from the radiator. Then, I purchased a fan shroud that should help keep the engine cooler. Next, I checked the thermostat on the stove by boiling it to make sure it was properly functioning. It opened exactly at 195 degree. Finally, I purchased a new mechanical gauge from Advanced Auto to double check my oil pressure.

I installed everything and started the engine. The engine started on the third crank. When the engine cranked up I had 50 psi of oil pressure (awesome)!! I ran the engine for a few minutes but am hearing a knocking sound. Thanks to your help, I believe the low oil pressure and temp mystery is solved but, I don’t have a clue what the knocking noise is. It seems to be coming from the #4 cylinder area but this is a guess as I am standing by my gauge cluster on the driver side. FE Gurus, what do you this could be. Is it my forged pistons or is a lifter? I look forward to your replies.

Respectfully,

Lance