Reason for 0 pressure
09-29-2008, 06:02 PM
#21
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I agree full force, it could certainly need more than a polish;
that would be best case scenario. You can't make a conclusion from looking at the pics. When I took out my mains due to high oil temps I had to get a new crank, so that happens too. One thing is for sure, oil temps need to be measured for both of you. Lean carburation can play a significant role in high oil temps as well as the oiling system itself.
BT
that would be best case scenario. You can't make a conclusion from looking at the pics. When I took out my mains due to high oil temps I had to get a new crank, so that happens too. One thing is for sure, oil temps need to be measured for both of you. Lean carburation can play a significant role in high oil temps as well as the oiling system itself.
BT
In my case I questioned oil pressure my story is a long one, took perectly good engines, polish cranks, new bearings then had issues, only thing different was I had standard pressure/volume oil pumps, I had 45-50 psi cold... did not seem like enough, most say that was fine, i disagree... I run 75 cold now with 40-50 after running hard at idle, I have no more issues... temps are monitored on my boat since also... runs no more then 190-200 ever so far..
My opinions are my own, i fixed my issues... Dave knows what I have been through and all the steps covered, I believe pressures/volume played a big role in my issues, then again I see a friends 1075's run 52 psi cold.... maybe different since they are dry sump but thats what they run..I would not feel that is enough in my opinion but Merc knows what they are doing and engines are monitored for problems, if too low they shut off.
likje I say, pressures are a matter of opinion..I still use 10 PSI per 1000 rpm as a rule..minimal..
09-29-2008, 06:36 PM
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I like the pressures a little higher too FF. I run HV pumps as well. Next time around though I'm going to tighten the lower end up a bit and run standard volume pumps.
I build my own engines as well and have done quite well over the years although I have learned the hard way a number of times. I just get a kick out of the "pros" that come on here and act like everyone is building power for super cat light race boats or something and have unlimited resources. If everyone threw out their rods, cranks, pistons, blocks, etc. everytime they found a little bronze in the filter, all the engine builders would be rich!! SShhhhshh.
I build my own engines as well and have done quite well over the years although I have learned the hard way a number of times. I just get a kick out of the "pros" that come on here and act like everyone is building power for super cat light race boats or something and have unlimited resources. If everyone threw out their rods, cranks, pistons, blocks, etc. everytime they found a little bronze in the filter, all the engine builders would be rich!! SShhhhshh.
09-29-2008, 06:43 PM
#23
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well you know without disassembly no one knows much...unless their cystal ball is working damn good...the oil will turn black like that when a bearing spins and the extra friction there will burn the oil up quick....then you have to figure out which happened first, did the oil look good up to the point the oil pressure started to drop ? did it get lower and lower or just drop to 0 at one time ?
09-30-2008, 01:05 AM
#24
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I like the pressures a little higher too FF. I run HV pumps as well. Next time around though I'm going to tighten the lower end up a bit and run standard volume pumps.
I build my own engines as well and have done quite well over the years although I have learned the hard way a number of times. I just get a kick out of the "pros" that come on here and act like everyone is building power for super cat light race boats or something and have unlimited resources. If everyone threw out their rods, cranks, pistons, blocks, etc. everytime they found a little bronze in the filter, all the engine builders would be rich!! SShhhhshh.
I build my own engines as well and have done quite well over the years although I have learned the hard way a number of times. I just get a kick out of the "pros" that come on here and act like everyone is building power for super cat light race boats or something and have unlimited resources. If everyone threw out their rods, cranks, pistons, blocks, etc. everytime they found a little bronze in the filter, all the engine builders would be rich!! SShhhhshh.
,I wouldn't get "mad" about someone telling it like it is from personal experience,yes,until motor is tore down no one will really know the true extent of the damage. I'm glad this guy can get it warranteed,Smitty
09-30-2008, 07:26 AM
#26
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I just know that when you see copper in a oil filter that it is a bearing, whatever the cause...
In my case I questioned oil pressure my story is a long one, took perectly good engines, polish cranks, new bearings then had issues, only thing different was I had standard pressure/volume oil pumps, I had 45-50 psi cold... did not seem like enough, most say that was fine, i disagree... I run 75 cold now with 40-50 after running hard at idle, I have no more issues... temps are monitored on my boat since also... runs no more then 190-200 ever so far..
My opinions are my own, i fixed my issues... Dave knows what I have been through and all the steps covered, I believe pressures/volume played a big role in my issues, then again I see a friends 1075's run 52 psi cold.... maybe different since they are dry sump but thats what they run..I would not feel that is enough in my opinion but Merc knows what they are doing and engines are monitored for problems, if too low they shut off.
likje I say, pressures are a matter of opinion..I still use 10 PSI per 1000 rpm as a rule..minimal..
In my case I questioned oil pressure my story is a long one, took perectly good engines, polish cranks, new bearings then had issues, only thing different was I had standard pressure/volume oil pumps, I had 45-50 psi cold... did not seem like enough, most say that was fine, i disagree... I run 75 cold now with 40-50 after running hard at idle, I have no more issues... temps are monitored on my boat since also... runs no more then 190-200 ever so far..
My opinions are my own, i fixed my issues... Dave knows what I have been through and all the steps covered, I believe pressures/volume played a big role in my issues, then again I see a friends 1075's run 52 psi cold.... maybe different since they are dry sump but thats what they run..I would not feel that is enough in my opinion but Merc knows what they are doing and engines are monitored for problems, if too low they shut off.
likje I say, pressures are a matter of opinion..I still use 10 PSI per 1000 rpm as a rule..minimal..
I agree with your assessment of your oil system. I think big block Chevy's should have 60 psi oil pressure warm running above 3000 rpm. That means you will have 80+ when cold. After a hard run my pressure stays above 20 and recovers quickly to about 40 at idle. This requires a number of things.
Clearences need to be correct. That means trial assembly and careful measurement with good micrometers and bore gauges. You don't just buy a rotating assembly and throw it in a block.
High volume oil pumps are almost always required. I like to run wider than stock clearences for less friction and greater oil flow to cool the bearings. Also on older blocks, the lifter bores wear and you lose more pressure there. More volume is required to keep the pressure up.
More oil flow requires an aftermarket deep oil pan with screens and a windage tray. The farther you can get the oil from the crank, the better. I put scrapers in my latest engines. This oil control keeps foaming under control and helps keep temps down.
A high volume pump won't do much good if you try to force that oil through 3/8 hoses and fittings. I'm using -10 hoses and fittings. That's equal to 5/8 i.d. Oil coolers also need to be upsized. A good size for a 500 hp engine is 3" dia. x 12" element. These coolers are advertised as 3" x 18" overall. I'm using 3" x 18" elements with 548 ci., 650hp+.
Tuneup is very important. Most oil heat come from the underside of the piston. Running lean or detonation causes the piston to get hot and that heat is transferred to the oil. Jetting a bit rich is a good insurance policy. Look at the way Mercruiser sets up their engines. Safe ignition timing is usually about 34 degrees total. I run 36 but I watch the plugs carefully and I run good premium gas. Keep the water temps cool. Mercruser used 140 degree thermostats in all of there carb. engines. Arizona Speed and Marine has 120 degree therms., thats what I use.
Last, good oil temp, oil pressure and water temp gauges are required. Ruining a $10,000 engine because you don't have a $50 oil temp gauge is pretty careless. Oil temps around 200 are great. 260 is kind of high and 280 should signal you to back off and let it cool. If you are seeing temps above 260, something is wrong with your oil system. I was having temp problems a few years ago and after one poker run, my fresh Mobil One would be black. Now that I have it under control, my oil looks almost new after a poker run. Quickly turning the oil black is a sign of too much heat on the underside of the pistons. Richening the mixture made my oil cleaner!
All of this is complicated and expensive. Sorry. Getting away from stock engines is going to require more money and more maintanence. These are a few of the things I've learned. I hope they can help someone else.
Last edited by PatriYacht; 09-30-2008 at 07:33 AM.
09-30-2008, 03:55 PM
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I agree with your assessment of your oil system. I think big block Chevy's should have 60 psi oil pressure warm running above 3000 rpm. That means you will have 80+ when cold. After a hard run my pressure stays above 20 and recovers quickly to about 40 at idle. This requires a number of things.
Clearences need to be correct. That means trial assembly and careful measurement with good micrometers and bore gauges. You don't just buy a rotating assembly and throw it in a block.
High volume oil pumps are almost always required. I like to run wider than stock clearences for less friction and greater oil flow to cool the bearings. Also on older blocks, the lifter bores wear and you lose more pressure there. More volume is required to keep the pressure up.
More oil flow requires an aftermarket deep oil pan with screens and a windage tray. The farther you can get the oil from the crank, the better. I put scrapers in my latest engines. This oil control keeps foaming under control and helps keep temps down.
A high volume pump won't do much good if you try to force that oil through 3/8 hoses and fittings. I'm using -10 hoses and fittings. That's equal to 5/8 i.d. Oil coolers also need to be upsized. A good size for a 500 hp engine is 3" dia. x 12" element. These coolers are advertised as 3" x 18" overall. I'm using 3" x 18" elements with 548 ci., 650hp+.
Tuneup is very important. Most oil heat come from the underside of the piston. Running lean or detonation causes the piston to get hot and that heat is transferred to the oil. Jetting a bit rich is a good insurance policy. Look at the way Mercruiser sets up their engines. Safe ignition timing is usually about 34 degrees total. I run 36 but I watch the plugs carefully and I run good premium gas. Keep the water temps cool. Mercruser used 140 degree thermostats in all of there carb. engines. Arizona Speed and Marine has 120 degree therms., thats what I use.
Last, good oil temp, oil pressure and water temp gauges are required. Ruining a $10,000 engine because you don't have a $50 oil temp gauge is pretty careless. Oil temps around 200 are great. 260 is kind of high and 280 should signal you to back off and let it cool. If you are seeing temps above 260, something is wrong with your oil system. I was having temp problems a few years ago and after one poker run, my fresh Mobil One would be black. Now that I have it under control, my oil looks almost new after a poker run. Quickly turning the oil black is a sign of too much heat on the underside of the pistons. Richening the mixture made my oil cleaner!
All of this is complicated and expensive. Sorry. Getting away from stock engines is going to require more money and more maintanence. These are a few of the things I've learned. I hope they can help someone else.
Clearences need to be correct. That means trial assembly and careful measurement with good micrometers and bore gauges. You don't just buy a rotating assembly and throw it in a block.
High volume oil pumps are almost always required. I like to run wider than stock clearences for less friction and greater oil flow to cool the bearings. Also on older blocks, the lifter bores wear and you lose more pressure there. More volume is required to keep the pressure up.
More oil flow requires an aftermarket deep oil pan with screens and a windage tray. The farther you can get the oil from the crank, the better. I put scrapers in my latest engines. This oil control keeps foaming under control and helps keep temps down.
A high volume pump won't do much good if you try to force that oil through 3/8 hoses and fittings. I'm using -10 hoses and fittings. That's equal to 5/8 i.d. Oil coolers also need to be upsized. A good size for a 500 hp engine is 3" dia. x 12" element. These coolers are advertised as 3" x 18" overall. I'm using 3" x 18" elements with 548 ci., 650hp+.
Tuneup is very important. Most oil heat come from the underside of the piston. Running lean or detonation causes the piston to get hot and that heat is transferred to the oil. Jetting a bit rich is a good insurance policy. Look at the way Mercruiser sets up their engines. Safe ignition timing is usually about 34 degrees total. I run 36 but I watch the plugs carefully and I run good premium gas. Keep the water temps cool. Mercruser used 140 degree thermostats in all of there carb. engines. Arizona Speed and Marine has 120 degree therms., thats what I use.
Last, good oil temp, oil pressure and water temp gauges are required. Ruining a $10,000 engine because you don't have a $50 oil temp gauge is pretty careless. Oil temps around 200 are great. 260 is kind of high and 280 should signal you to back off and let it cool. If you are seeing temps above 260, something is wrong with your oil system. I was having temp problems a few years ago and after one poker run, my fresh Mobil One would be black. Now that I have it under control, my oil looks almost new after a poker run. Quickly turning the oil black is a sign of too much heat on the underside of the pistons. Richening the mixture made my oil cleaner!
All of this is complicated and expensive. Sorry. Getting away from stock engines is going to require more money and more maintanence. These are a few of the things I've learned. I hope they can help someone else.
Now I run .003 on mains, .0035 on rear main both engines, rods are .0025 I believe, I have it logged at home., I shimmed the spring in the oil pumps.095 to give more pressure, seems to work great!
I am runn ing TRS bell housing oil coolers, were 7 blade, now they are 8 blade (both new). temps are great, tune is good.
I have stock 5/8 TRS lines, they measure 1/2 inch I.D. they are fine for my setup.
I have learned alot about BBC this year (I am a Ford guy) and will share any info I can to help Dave or anyone else! I have been through this too!
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