swelebny Posted December 12, 2005 Share Posted December 12, 2005 A week or so ago several folks helped answer a question I had on buggered threads in the water pump.... Thanks.... I removed the oil pump on my wife's 1995 188,000 mile car, retorqued the screws that had backed out quite a ways, resealed the pump and reinstalled with a new o-ring. (no gasket, just the anaerobic sealant! That was a first...) The oil light comes on the when the engine is warm, even above 2000 RPM. My wife drove the thing an hour with the light on. I figured I had messed up on the oil pump and she finished off the engine. The strange thing is, the engine is dead quiet and doesn't appear to be in any distress at all. This motor had a lifetime of oil changes every 3000 miles. Am I right in thinking that lifter noise is a pretty accurate indicator of oil pressure on these little engines? The motor is silent at speed and at idle. What gives? I'm confused.... Steve Quote Link to comment Share on other sites More sharing options...
tunered Posted December 12, 2005 Share Posted December 12, 2005 i think i would hookup a manual oil pressure gauge first and go from there. Quote Link to comment Share on other sites More sharing options...
nipper Posted December 13, 2005 Share Posted December 13, 2005 i agree, get a cheap mechanical gauge, or a better one if you want to mount it for good, and see what it is. Can be the oil pressure switch is bad, they are not the nost sophistacted peices of equipment. nipper Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted December 13, 2005 Share Posted December 13, 2005 It's possible some gunk got stuck in the oil pressure switch. Let's hope that's what happened, or that it's bad, because the oil light comes on when oil pressure is in the single digits. If the engine was run that long with that low of oil pressure....bad things are sure to happen. Quote Link to comment Share on other sites More sharing options...
Suzam Posted December 13, 2005 Share Posted December 13, 2005 Yeah, I agree with Josh. However after that amount of time, if the engine was quiet with the light on I'd bet your pressure was OK. However don't roll those dice too much more. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted December 13, 2005 Share Posted December 13, 2005 We once owned a Colt Vista Wagon that had the oil sender switch begin leaking. So I put in an aftermarket one. Got the oil light (BTW - I guess we're gonna use that crazy Aladdin's lamp symbol for a few more generations huh? Isn't that left over from steam locomotive days?) and talked to a mech about the issue. Seems some oil pressure senders have very tiny openings that get clogged easily if some gunk is disturbed in just the right part of the 'circulatory system. And, after getting a look at 3 brands, I could immediately tell a difference. So, yeah, either gunk in the switch or possibly bad wiring? Quote Link to comment Share on other sites More sharing options...
Gnuman Posted December 13, 2005 Share Posted December 13, 2005 I'll add my vote that the sender is bad, or the wire attached to it is unplugged (look just above the oil pump, to the left as you are facing the engine from in front of the car. There is a sender with a single wire attached to it, that is the Oil pressure sender that we are talking about.) If the wire is not attached, or the ground is not good to that part of the engine, you will get a false oil light. Also the sender may have picked that particular time to fail just to mess with you. . . Quote Link to comment Share on other sites More sharing options...
subie94 Posted December 13, 2005 Share Posted December 13, 2005 don't really mean to hijack the thread,but seeing that we're talking about oil pressure an all.couldn't see starting another one.(of course i could of done a search) is it possibly to use the stock oil pressure sending unit to get a reading for a aftermarket pressure guage.i have the guage all mounted and i'm planning on just tapping into the wire going to the sending unit for the oil light. would that work? or would i get a bad reading? Quote Link to comment Share on other sites More sharing options...
nipper Posted December 13, 2005 Share Posted December 13, 2005 don't really mean to hijack the thread,but seeing that we're talking about oil pressure an all.couldn't see starting another one.(of course i could of done a search) is it possibly to use the stock oil pressure sending unit to get a reading for a aftermarket pressure guage.i have the guage all mounted and i'm planning on just tapping into the wire going to the sending unit for the oil light. would that work? or would i get a bad reading? the light is an on/off signal to ground. Its a switch. You need a variable signal to make a gauge work. You can tee into there the sending unit is for the switch. nipper Quote Link to comment Share on other sites More sharing options...
subie94 Posted December 13, 2005 Share Posted December 13, 2005 ok thanks for the info Quote Link to comment Share on other sites More sharing options...
swelebny Posted December 13, 2005 Author Share Posted December 13, 2005 Thanks for the responses fellas. This was my first time using the anaerobic sealant. As I understand the stuff, the excess gets 'washed' away. I wonder if it is possible that some excess sealant got up into the sending unit? That sounds like a bit of a stretch..... Anyone heard of that happening? Still can't believe a hot engine with no oil pressure has silent lifters..... Steve Quote Link to comment Share on other sites More sharing options...
idosubaru Posted December 13, 2005 Share Posted December 13, 2005 have you checked the pressure sender wiring/connector yet? i haven't seen anything saying you've checked that. complete loss of oil doesn't make the lifters noisey (at least in the instance that i experienced), so i would imagine low pressure could easily slide through with little to no indication either. i hit some firewood in the interstate a couple weeks ago. ripped all my exhaust off the car and dented my trans pan pretty good. everything else looked good and i didn't see anything leaking, so i continued to work. no noise, no nothing, car ran fine. next day or two the motor locked up. again, no noise right up til it locked up. no oil....i'm guessing there was a small leak (as i had put a couple hundred miles on it in that day or two)...in the oil filter or pan or the pan is dented enough to restrict the sump. the oil pump is brand new and the engine was compeltely resealed this summer. now it's locked up, havent even looked at it yet. i towed it home and am putting another motor together, heads were just finished at the shop. so..like i said, complete loss of oil doesn't have to cause lifter noise, i wish it would have in my case. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted December 13, 2005 Share Posted December 13, 2005 have you checked the pressure sender wiring/connector yet? i haven't seen anything saying you've checked that. complete loss of oil doesn't make the lifters noisey (at least in the instance that i experienced), so i would imagine low pressure could easily slide through with little to no indication either. i hit some firewood in the interstate a couple weeks ago. ripped all my exhaust off the car and dented my trans pan pretty good. everything else looked good and i didn't see anything leaking, so i continued to work. no noise, no nothing, car ran fine. next day or two the motor locked up. again, no noise right up til it locked up. no oil....i'm guessing there was a small leak (as i had put a couple hundred miles on it in that day or two)...in the oil filter or pan or the pan is dented enough to restrict the sump. the oil pump is brand new and the engine was compeltely resealed this summer. now it's locked up, havent even looked at it yet. i towed it home and am putting another motor together, heads were just finished at the shop. so..like i said, complete loss of oil doesn't have to cause lifter noise, i wish it would have in my case. THAT....is a nmad shame. hope you get back on the road soon. Quote Link to comment Share on other sites More sharing options...
swelebny Posted December 13, 2005 Author Share Posted December 13, 2005 Thanks for the reply Gary.... By the way, there's a reason I'm trying to figure this out 'theoretically'. I just injured my back and I've GOT to quit working on things for a little while. The sender is working just fine, in that when cold (10F) the oil light extinguishes and doesn't come on again until the engine is up to operating temperature. Once warm, the oil light comes on below 2000 RPM. It sounds as if your failure after hitting the wood came from an abrupt loss of all oil after the last of it dribbled out over a couple days.... Sounds like it happened pretty quick too. Maybe all the more reason to think I've still got oil pressure if my wife didn't trash the thing afetr the hour's drive. So I guess the original question still stands, can these things really have no oil pressure for extended periods of time and quiet lifters? The first thing you here on my old plow truck when the oil level is down is the lifters. Even with good oil pressure on the gauge.... Thanks guys.... Steve Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted December 13, 2005 Share Posted December 13, 2005 You may still have oil flow, but low pressure. If you're getting some pressure at idle, and "normal" pressure at higher rpms to fill the lifters, and the lifters don't leak....I wouldn't necessarily say they are going to make noise. If the sender is working correctly, what I'd lean towards is the o-ring between the block & oil pump not being aligned/installed properly during the oil pump work. I'd recommend pulling the oil pump back off and checking things. Quote Link to comment Share on other sites More sharing options...
swelebny Posted December 13, 2005 Author Share Posted December 13, 2005 Any pearls of wisdom on keeping the o-ring in the correct position during reassembly? I had a heck of a time lining up the pump and was actually worried it had moved on me..... Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted December 13, 2005 Share Posted December 13, 2005 put a little vasoline in the hole and on the o-ring. That should help keep it from moving. That or everything needs to be relatively dry/clean and the o-ring should stay put. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted December 13, 2005 Share Posted December 13, 2005 THAT....is a nmad shame. hope you get back on the road soon. thanks ,and i should....already had another good motor ready to go. but i tore it down and am resealing from the block up before i install it. machine shop is done with the valve job, machine of the heads so i just need to slap them and the cams on and i'm good to go. not fun doing it twice in a year, but what do you do? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted December 13, 2005 Share Posted December 13, 2005 So I guess the original question still stands, can these things really have no oil pressure for extended periods of time and quiet lifters? the answer is "yes". i don't think anyone will be able to tell you exactly how long it will be before they start making noise. 10 miles, 100 miles, 1000 miles, 10,000 miles, who can answer that definitively? and i don't think you have "no" oil pressure, you have some. some at higher rpm's and who knows what at low. so at least the higher rpm driving will keep the lifter lubricated and pumped up it seems. but i also don't think you can get much further than speculation on this. Quote Link to comment Share on other sites More sharing options...
swelebny Posted December 13, 2005 Author Share Posted December 13, 2005 "but i also don't think you can get much further than speculation on this." Agreed.... Time to get some real data. Steve Quote Link to comment Share on other sites More sharing options...
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