Oil Pressure Concern on rebuilt 355
Joined: May 2006
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Autozone,Oreilly part, or NAPA...I can't recall which one because I've bought sveral different sensor's and things from them during this rebuild. I think autozone though. If the sending unit is bad does that mean the reading would be fucked up but yet at the same time I'm getting suffeicent oil through out the motor or what????? Help is appreciated at this point considering I have about $5000 rapped up in this motor! Don't want to be ******* **** up at this point!
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try a different OSU. i bought one for my car because mine was reading a little low (trans shop put one in after they broke it) and the one i got from AZ was pure JUNK. every time i let off the gas under 20mph it would immediatly drop to 0 and throw a CG light. i was sitting at a light with absolutely no oil pressure on the gauge. i put the other one back in and it was a lot better (around 10-12psi at hot idle) and even then i still think that gauge reads low since i never had a single oil pressure problem until the trans shop broke my original OSU and replaced it.
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So you fell I'll be good with a mail order tune from mad Z28 or mad tuner now, Ion Sultan! Good guy to work with for sure. I should be good with this tune right for the WOT???? I'm sure a dyno tune would be better for sure although pricey at the moment! I'm sure I can pick up some more #'s with a dyno tune for sure!
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Modified socket or a particulat size. When I installe the motor I removed and installed it with an adjustable whrench. I'm sure it's a pain in the ***. I can't get my forarms under the intake and dash without scrapping and scrathing the **** out of them. Big for arm's I guess or not enough room, lol! See what weights do for you! Not allow you to install spark plugs and OSU's!!!!
Joined: May 2006
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From: somewhere that doesn't get snow
Modified socket or a particulat size. When I installe the motor I removed and installed it with an adjustable whrench. I'm sure it's a pain in the ***. I can't get my forarms under the intake and dash without scrapping and scrathing the **** out of them. Big for arm's I guess or not enough room, lol! See what weights do for you! Not allow you to install spark plugs and OSU's!!!!
Ok..... I was agreeing with the pressure sensor untill you said one thing....."the pressure drops under acceleration". Lets run a quick check list on this thing:
1. Is the oil pan full of oil or is it low on oil. I have seen motors that suck air and loose oil pressure under acceleration becuase of this.
2. When the oil pump pick up was installed was it measured to be 1/4" off the bottom of the pan or so and was it either bolted or welded in place
3. PUT A MECHANICAL GAUGE ON IT!!!--- Do this immediatly before you even think about starting it up again. No oil pressure will destroy a motor in a matter of seconds and then you have a nice looking paper weight.
4. Did you mess with the pressure spring when you installed the pump or did you just take it out of the box and install it.
5. Do you have any type of excessive lifter noise (Ticking, clicking, sewing machine noise)?
6. How did your machine shop clearance the engine, did you check the clearances upon assembly? Is 5w30 enough? What did the machine shop recommend to run for oil?
Also as for the fram oil filter, I have one on my 600+hp 8000rpm 385c.i. LT1 that I beat the **** out of on the street and the track. I also have one on my 06 GTO and my pickup truck. This cannot be cuased by an oil filter. Even if the filter was clogged the bypass would turn on and you would have higher oil pressure! K&N filters cost double the price because they say K&N on them and can actually clog easier becuase they filter such small particles and then the bypass will enable and you wont even be filtering any oil! Again from one LT1 guy to another put a mechanical gauge on it before you even think about sticking the key in the ignition again.
1. Is the oil pan full of oil or is it low on oil. I have seen motors that suck air and loose oil pressure under acceleration becuase of this.
2. When the oil pump pick up was installed was it measured to be 1/4" off the bottom of the pan or so and was it either bolted or welded in place
3. PUT A MECHANICAL GAUGE ON IT!!!--- Do this immediatly before you even think about starting it up again. No oil pressure will destroy a motor in a matter of seconds and then you have a nice looking paper weight.
4. Did you mess with the pressure spring when you installed the pump or did you just take it out of the box and install it.
5. Do you have any type of excessive lifter noise (Ticking, clicking, sewing machine noise)?
6. How did your machine shop clearance the engine, did you check the clearances upon assembly? Is 5w30 enough? What did the machine shop recommend to run for oil?
Also as for the fram oil filter, I have one on my 600+hp 8000rpm 385c.i. LT1 that I beat the **** out of on the street and the track. I also have one on my 06 GTO and my pickup truck. This cannot be cuased by an oil filter. Even if the filter was clogged the bypass would turn on and you would have higher oil pressure! K&N filters cost double the price because they say K&N on them and can actually clog easier becuase they filter such small particles and then the bypass will enable and you wont even be filtering any oil! Again from one LT1 guy to another put a mechanical gauge on it before you even think about sticking the key in the ignition again.
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I must have missed the part about it dropping under accel, could be the pick up tube fell off. Mine is welded to the pump 
!!!
I wouldnt drive it untill you get the mechanical gauge on it! If that checks out ok, get Napa or GM sensors. Once thats taken care of get that bitch on the street and let it rip.
Seriously I had mine WOT within 2 miles and within 50 it was already on the dyno.
I also used 15w45 Rotella for break in and Im still using it. Im sure that helps keep pressure up a bit and Rotella is suppossed to be great oil.
!!!I wouldnt drive it untill you get the mechanical gauge on it! If that checks out ok, get Napa or GM sensors. Once thats taken care of get that bitch on the street and let it rip.
Seriously I had mine WOT within 2 miles and within 50 it was already on the dyno.
I also used 15w45 Rotella for break in and Im still using it. Im sure that helps keep pressure up a bit and Rotella is suppossed to be great oil.
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Well I had the machine shop install the oil pump and he told me that he welded the pickup for the proper clearance. He had my oil pan, new timing chain set and all of my internals, and returned a short block to me. I will be installing a mechanical guage on it when I get back home for sure. Where's everyone buying this from???? The oil is right at the max peak as far as level and it's still clean as hell. I'm running 5w30 gastrol for my break in. I plan to switch to royal purple or AEMS oil after break in but some folks are making it out to be like I'm ready for WOT! I have right about 150 miles on it. The machinist did gap my rings for 150 shot! This was crucial information from what he said! I have no noise from the valve train. I'm running comp promag's NSA and guide plates and I adjusted right at 3/4 turn! Seems to be a perfect adjustement considering I've heard to go 1/2 to 1 full turn. Not sure guys. I really can't imagine that the pump being bad as much as I can for see the OSU being bad. I'll be changing that out as well since it was from the zone. Hopefully I can get this problem solved because this is the last thing I want to worry about. I also don't think my fans are coming on either but my temp stays right at about 175.....Are my fans not coming on because I completly removed all a/c and heat components from under the dash. would any of this take an effect on the fans because I heard something about turning on the a/c to ge the fans to come on all though my **** is gutted! Just curious! Thanks for the input guys!
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I must have missed the part about it dropping under accel, could be the pick up tube fell off. Mine is welded to the pump !!!
I wouldnt drive it untill you get the mechanical gauge on it! If that checks out ok, get Napa or GM sensors. Once thats taken care of get that bitch on the street and let it rip.
Seriously I had mine WOT within 2 miles and within 50 it was already on the dyno.
I also used 15w45 Rotella for break in and Im still using it. Im sure that helps keep pressure up a bit and Rotella is suppossed to be great oil.
!!!I wouldnt drive it untill you get the mechanical gauge on it! If that checks out ok, get Napa or GM sensors. Once thats taken care of get that bitch on the street and let it rip.
Seriously I had mine WOT within 2 miles and within 50 it was already on the dyno.
I also used 15w45 Rotella for break in and Im still using it. Im sure that helps keep pressure up a bit and Rotella is suppossed to be great oil.
Definitly put a mechanical gauge on it, and get your sensors from napa or gm. AZ **** is junk. Anytime I ever get anything form them its faulty or doesnt work the same.
On my 355 its like at 70 cold, 50ish at idle and 80 wot.
For break in I let it idle for 25min, changed oil and filter, then drove it around to make sure there were no leaks + goin WOT a few times to check oil pressure and seat the rings then drove it to speedinc to slap on the dyno, to really seat the rings good.
On my 355 its like at 70 cold, 50ish at idle and 80 wot.
For break in I let it idle for 25min, changed oil and filter, then drove it around to make sure there were no leaks + goin WOT a few times to check oil pressure and seat the rings then drove it to speedinc to slap on the dyno, to really seat the rings good.
You are ready for WOT once you get the oiling issue figured out IMO. If something mechanical inside is gonna break, its gonna break regaurdless and 99% of guys like to seat the rings hard.
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Do you think I should loosen them and then re adjust for a 1/4 turn after zero lash. Is my **** to tight. If they are to tight then the valves would be opening faster and not closing all the way correct? Would I be able to tell if I had them to tight. Didn't really seam to tight. I can still wiggle them a tad bit by hand with no load.....Zero lash is right when the pushrod stops turning in your fingers when your just starting to tighten them up correct....I did no preload or anything like that. Just pushrod stopped turning and then added 3/4 turn! Cranked right up just fine and i have no noises what's so ever! As for the bearing thing goes. All new bearings where installed of course , when I cut open my 2 filters I seen nothing out of the norm. Some metal shavings but NO copper looking shavings. I was told that this would be an indication of bearing failure....
zero lash is the instant the PR has no up or down play and you just start to feel some resistance while spinning them by finger. If you tightened them untill you couldnt spin them by hand anymore and then an extra 3/4 turn Id say thats too much. If it will beak anything Im not sure, might cause alot of valve float
Last edited by AChotrod; Sep 29, 2009 at 06:10 PM.
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zero lash is the instant the PR has no up or down play and you just start to feel some resistance while spinning them by finger. If you tightened them untill you couldnt spin them by hand anymore and then an extra 3/4 turn Id say thats too much. If it will beak anything Im not sure, might cause alot of valve float
Then to the oil matter! They said as well to go with a mechanical guage first thing due to electronic guage failure possibilities. They have seen this as well. The also recommended the next step would be to swap out the oil sending unit....Worst case scenario the pump may be bad but doubt full. I asked about the bearings as well and they told me they used H series race bearings and that I would diffently be able to tell if I had those going bad. Since there a harder bearing that I would see junks more or less rather than shavings from initial start up. They said if I didn't have much in the first 2 filters that it wasn't bearings. I'll be back next month I said I'll bring a my filter to them and they will cut it open with this machine and they'll take a look. With no noises or anything acting up they said it's diffently not bearings. So it's a waiting game. Where is everyone installing these mecahnical guages both on the motor and in there cars????? pictures would be great, I love new ideas. Plus not sure exactly where to install or where every one ran them to! Where exactly on the motor? i was thinking about installing it in the council by the cigeratte lighter, that gapping hole. Id have to modify a little wall/plate thingy but ideas are great.. thanks guys
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my new 358 has 80 miles on it ,im runnin rotella 15-40 with a delco filter .cold im runnin 75-80 lbs of pressure ,warmed up in gear at idle im at 40 w.o.t it goes to 85 im runnin the clevite 77 series bearing with a 2 thou clearance wit a melling stand volume stan pressure pump i started hammerin on it after 50 miles and so far pressure is the same as it was new .like stated before do a mech test on it only real way to see what its doin ,get rid of the fram filter on more than one occasion at the shop we have done a l.o.f wit a fram "as it was late and thats all we could get " we had no pressure switch to a purolator or other and it was fine .i would also try a thicker oil in it depending on the air temp and how hard ya drive
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my new 358 has 80 miles on it ,im runnin rotella 15-40 with a delco filter .cold im runnin 75-80 lbs of pressure ,warmed up in gear at idle im at 40 w.o.t it goes to 85 im runnin the clevite 77 series bearing with a 2 thou clearance wit a melling stand volume stan pressure pump i started hammerin on it after 50 miles and so far pressure is the same as it was new .like stated before do a mech test on it only real way to see what its doin ,get rid of the fram filter on more than one occasion at the shop we have done a l.o.f wit a fram "as it was late and thats all we could get " we had no pressure switch to a purolator or other and it was fine .i would also try a thicker oil in it depending on the air temp and how hard ya drive