SRT10KLLR

iTrader: (11)

I just had a 408 installed and when we went to crank it over it had no oil pressure. First the relay for the fuel pump was removed to turn over the engine a little to get oil up top with no possibility of starting. Then the relay was put back in and the fuel pump was primed. The engine started right up but was quickly shut off because there was no oil pressure.

What could be causing this?

N4cer

iTrader: (11)

You have NO oil pressure? Or LOW oil pressure? Just making sure.
If NO oil pressure, here's some of what I'd do, but I know very little:
- make sure you have oil in it (stupid but I forgot coolant once)
- make sure you didn't break your oil pressure sending unit while installing intake
- pull front cover and make sure the oil pump is turning
- check oil ring on oil pump (but it would still have some pressure)
- check barbell plug in back of motor (again would still have pressure)
- pull it apart and check the bearings

SRT10KLLR

iTrader: (11)

No oil pressure.

The engine builder suggested the following:

1. Pulling the oil pan to check that the pickup tube is not to close/far to the bottom of the pan.

2. Remove some bolt/cover on the front of the engine to see if the oil pump was working.

BTW, it did have oil(6 qts).

SRT10KLLR

iTrader: (11)

Any other suggestions that do not require removal of all the accessories, timing cover etc. and/or removal of the engine from the vehicle?

N4cer

iTrader: (11)

I can't see how there could be any man. Make sure your oil pressure sending unit is plugged in is the only one.

It's a new motor isn't it? Part of it is sometimes you gotta pull it back out. It's the name of the game. This isn't rare.

Jon5212

iTrader: (2)

I'd be having your engine builder do that for you....

SRT10KLLR

iTrader: (11)

The engine builder will probably say it was an install error and the installer will say it was builder error. That leaves me footing the bill, lol.

I will cross my fingers and hope that it can be fixed without removal.

bgblockelcamino

iTrader: (9)

check the plate above the oil filter. knew someone who took the cooler off and made a block off plate. but that is actually a oil passage. just a thought

Steve Bryant

iTrader: (1)

Here's a thread where I helped a guy go through the no oil pressure troubleshooting process. Please give it a read and think it through.

https://ls1tech.com/forums/showthrea...t=pressure+oil

Steve

Haans249

iTrader: (24)

First off, how long did you leave the motor running? My brand new motor took a few seconds to build pressure, and at first I was very tempted to shut it off right away, but knew it had to prime all the oil lines throughout the entire engine to build the pressure. If you started it, and shut if off right after you started because it didn't have any pressure, you might want to leave it for about 3 seconds before it will really build the pressure. IF it doesn't build any pressure after about 3 seconds, then you DEFINITELY have a problem. Did you install the oil pump/pick-up tube? or was that all installed when you got the motor? If you installed it, make sure you didn't pinch the pickup tube gasket. But first, like was mentioned above, you need to check the oil pressure sending unit first to make sure its not broken and or plugged in.

Good Luck!

slow trap

iTrader: (22)

it took mine quite a while to build up pressure while cranking it over,probably 10-15 seconds on a rough guess.if i was you i'd go back and crank it for atleast 5 seconds without the fuel pump fuse in and see if it starts to build pressure. if you have already cranked it over longer than i had to something is wrong.

edcmat-l1

iTrader: (10)

Plastic dumbell in the back of the block, and the 5/8 freeze plug in the front. Seems like alot of people forget these. Esp builders new to the LS motors.
PS, how did you prime the pump? Did you fill the filter?

SRT10KLLR

iTrader: (11)

I read that and will try trouble shooting it from step one. Thanks, I appreciate the help. Can I call you for tech help, lol.



The only thing we tied so far was to remoe the oil pan to check that the pick up tube was 3/8" from the pan. I will try the steps above to continue though.


I did not build the motor but the guy who did builds a lot of LS motors. The filter was filled and 6 quarts were put in the engine. We primed by removing the fuel relay and cranking a couple of seconds the letting the starter cool and doing it again. Then we cranked it up with the fuel relay installed and it started right up but had no oil pressure for 10 seconds so we shut it down. You could hear the valve train noise pretty good during the initial start up.


At what point does damage occur to the engine by cranking with no oil pressure?

Steve Bryant

iTrader: (1)

SRT10KLLR,
If you do want to call me to discuss things, send me a PM.

Best of Luck with this. Assuming things were properly lubricated during assembly, a few seconds (10 to 15 seconds cumulative maybe more) probably won't hurt anything.

Steve

racer7088

No oil pressure for 10 seconds isn't that good for anything but it still might not have hurt anything either since there's no load on an engine just idling. The thread Steve Bryant linked you too has all the plugs and stuff that could be out or whatever.

I've seen many LS1 engines not want to prime initially but usually when started they get pressure right away. I try and oil up the new pumps and this seems to help a bit with them priming up faster. Your builder should be able to go through the list of what could be wrong or missing.

I've talked people through this too with engines they did themselves and have had missing plugs etc.but yet they still ran fine once these problems were fixed since they never ran the engine under load with no oil pressure. There should be some prelube on the bearings, pistons and rings etc. which will certainly last for just cranking the engine over and running a few seconds under no load.

SRT10KLLR

iTrader: (11)

I will try the suggestions after Christmas. My engine builder and a fellow forum member also mentioned using a dry oil filter rather than one full of oil.

Steve Bryant

iTrader: (1)

Before you try the dry filter, I'd try backing out the left front side oil galley plug almost all the way. That way, the oil pump doesn't have to push oil through the filter or anywhere else for that matter. Crank the engine only (fuel pump relay removed). The oil should come out pretty quickly if the oil pump is able to pump oil. If no oil comes out, I'd pull the front cover and check the O ring in the pickup tube, that the pump outlet is flush with the block and that the front "freeze plug" is in place. Even if the pickup tube is nearly against the bottom of the pan, at cranking RPM's you should be able to pump oil out this side galley plug. I think that improper O ring sealing is probably the leading cause of no oil pressure.

Steve

HTMtrSprt

What I haven't seen mentioned yet is to remove all the plugs from the motor so there is no compression load on the bearings or wrist pins. The engine will also spin faster this way which may help get the oil pump to prime if lack of prime is the problem. I have always been able to get oil pressure this way before firing the engine up the first time. FWIW - the oil pump should always be assembled with assembly lube or light grease to insure that it primes quickly.

Whistler

iTrader: (46)

Are you running a double roller timing chain?

bjamick

iTrader: (31)

So any updates? And the plug idea is a great idea to keep your parts safer by putting no load on them. Bravo ..