just rebuilt a lq4 and it wont make more that 20 pounds at idle and when it warms up its about 7 pounds ive changed the seal and the oil pump and nothing
any advice?
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just rebuilt a lq4 and it wont make more that 20 pounds at idle and when it warms up its about 7 pounds ive changed the seal and the oil pump and nothing
any advice?
Replace the cam thrust plate if the seal is damaged or warped. Another thing I've started doing is putting a bead of silicone around the pickup tube between the oring and the swedged metal bead. Be sure to let the silicone set up for at least two hours before starting the engine so the silicone has time to harden a little.
thats a loaded question. can be so many variables. wrong cam bearings, wrong main bearings, bad O ring, pump not sealing to block, oil passages clogged
Dont forget the "forgot to install the dogbone" into the oil galley at the back of the engine.
i used gasket sealer on the oring and the cam bearing and rod bearings are brand. new cam bearings are from the dealership. the thrust plate stayed in a box the entire time the motor was apart.never plled the dogbone out of the motor. when i changed the seal the second time(with the motor in the truck) i had to clean a lot of gunk out of the pickup tube. im think maybe the oil prssure sending unit might be clogged so im about to pull it out and check it
new bearings dont mean anything if they arent properly matched to the crank. a polished or cut crank needs over sized bearings. if you didnt have this done to crank are you sure the crank didnt need checked?Quote:
Originally Posted by danger_ranger83
the sensor is reading so i woudl rule the sensor out
the rod bearings only got changed bc the motor blew a head gasket and the bearings didnt look goodQuote:
Originally Posted by Quik
so there is NO way the sending unit could be the problem?
if the rod bearings didnt look good then the crank is tore up then. having poor tolerances with rod-crank bearings will also cause low oil psiQuote:
Originally Posted by danger_ranger83
the rod bearings werent tore up they just had nasty spots where the water was sittingQuote:
Originally Posted by Quik
Even with a new o ring on the pick up, you can still put it in wrong and pinch the o ring. Do what i did and cut a little section out of the two pick up tube brackets so you can move it around and get the oring to sit right.
what color O ring are you using?
wheni put the pickup tube on i put it in the oil pump and tightened it down before i put it on the motor
im using the black seal that came with the oil pump which is the same as the blue one from dealership
blue is for Fbodys brown/red are for trucksQuote:
Originally Posted by danger_ranger83
i had that problem with my 408.
http://i172.photobucket.com/albums/w...s/Oring002.jpg
http://i172.photobucket.com/albums/w...s/Oring001.jpg
http://i172.photobucket.com/albums/w...s/Oring003.jpg
http://i172.photobucket.com/albums/w...s/Oring004.jpg
on the paper that came with it it says to use the red one with a tube that is flared at the end and the blue one for a tube that is smooth. i had a blue seal in there the first time it didnt have pressure and replaced it with a red seal and still didnt fix the problem then replaced the oil pump and same problem stillQuote:
Originally Posted by Quik
im not tryin to argue thats just what it says to do.. thank u for the advise i guess im gonna tear it down tonight and change the cam bearings and while i have it apart ill make sure which seal is in there
ever heard of someone changing the cam bearings with the motor still in the truck? :confused:
I don't believe that is even possible. Do you know what PN and brand of bearings you put in there? There are two sizes, one for 2004 and earlier and the other for 2005 and later, if I remember correctly. They will not interchange is what I was told by my builder. Do you heads have all 10 head bolts the same length or are the two outer ones under the valve cover shorter? You can check to see if the pump is working properly by making an aluminum block off plate to go between the oil pan and the return plate that is above the oil filter. Drill a hole in the block off plate so that oil can enter the return cover (front hole) and tap the cover for a manual gauge. Pull all the plugs out and disconnect the fuse to the injectors or just disconnect them. Get someone to crank the engine until you start showing oil pressure. I actually started my old engine for a few seconds and it had 60 psi of oil pressure. When I removed the cover and put it back to normal I only had 15 psi, with 20w50 oil! While assembling my rebuilt engine I noticed my cam retainer plate had a cut in the silicone so I replaced it. Same engine that had 15 psi with 20w50 now has 60 with 5w30. Inside your oil pan by the oil filter, does your pan have a pressure relief valve built into it like the new pans do?
the motor is a 99 the outer head bolts are shorter the pump is brand new so idk what to do what do u suggest?Quote:
Originally Posted by RedHeartbeat
pulled the retainer plate off and its not ripped anywhere but in some places the seal is kinda smashed and doesnt stick out looks like it wouldnt seal very good
i guess its not gonna make oil pressure no matter what i do
so out comes the motor for some new cam bearings
ill take it to the machine ship this time
ok well im pullin the motor and i went to pull the cam out and it wont come out its like its hitting something
you rotated the cam a few revolutions and its still hitting something? Did you pull the cam sensor? Sometimes they hang on it. If you rotated the cam, lifted the sensor and its still hanging on something you'll have to get some dowel rods to hold the lifters up, one of them isn't being held tight enough in the lifter carriers.
i still think you knocked a cam bearing out of the journal, or moved it
its got dowel rods holding the lifters up just pulled the cam sensor..didnt help it slides backwards but wont come forward at all..
what happens if it wont come out either direction?
all this was with dowel rods in it? pull the rods, rotate the cam and then try to pull it. You're pulling the engine anyway, worry about it once its out.
alright so u think its a cam bearing?
ok figured the problem out number 2 cam bearing was too far forward and got smashed down by a lifter thats y the cam wouldnt come out and oil was seepin out where the bearing was smashed
theres your oil pressure issueQuote:
Originally Posted by danger_ranger83
yea im so glad that was the problem and it didnt mess the cam up any