Oil consumption?

[texasmike]

Does anyone know what the average/acceptable oil consumption might be for a 5.0L "H" series engine with 65k miles? When I started work on this original and stock truck (52.4K), a compression check showed #1 @ 175 and the remaining cylinders @ 180-190 psi. A small amount of soot accumulates in the tail pipe but there is never any visible smoke on startup or while driving, even when I open the secondaries. Early on, I replaced all sixteen valve guide seals. It currently uses about a quart between oil changes every 3-3.5k miles.The truck runs and shifts GREAT! However, there is quite a bit of wear on the right side of the brake pedal.

 

[Frankenchevy]

Does anyone know what the average/acceptable oil consumption might be for a 5.0L "H" series engine with 65k miles? When I started work on this original and stock truck (52.4K), a compression check showed #1 @ 175 and the remaining cylinders @ 180-190 psi. A small amount of soot accumulates in the tail pipe but there is never any visible smoke on startup or while driving, even when I open the secondaries. Early on, I replaced all sixteen valve guide seals. It currently uses about a quart between oil changes every 3-3.5k miles.The truck runs and shifts GREAT! However, there is quite a bit of wear on the right side of the brake pedal.

Looks like more brake pedal wear than expected for 50,000mi.

Whether it’s 50k or 150k, your compression looks high. I’d think it’d be closer to 125-135 psi.

180psi is L88 type numbers (12.5:1 CR).

Burning a quart between 3000mi OCIs isn’t terrible, but it’s not great either.

 

[DoubleDingo]

Wasn't the truck a delivery vehicle or dealer owned? I'd suspect heavy brake pedal wear if it was all stop and go. But a quart between changes is a tad high.

Have you ran any type of crankcase cleaner through the engine? I use motor purr tune-up maybe once a year or three. Pour it in, idle the engine for 20 minutes, drain the oil and see all the black deposits it cleaned off the innards. Fresh oil and filter, and the fuel system cleaner for the top side. Maybe some sticky rings on yours?

 

[texasmike]

The truck was purchased new by a construction company for the owners dad to run errands and check on the field crews from time to time. It was also used as a spare while other company trucks were being serviced or repaired. I went to work for the company in February 1992 and have most of the paper work for the truck. When the truck was paid off (36 months) the owner transferred the title to his dad and the odometer showed 10.7k at the time. His dad passed in 1988 and about a year later, the truck went to our Austin office and eventually ended up at the owners ranch. It later came back to Conroe and was parked outside in our yard in 2005 where it sat until 2018 when the title was transferred to me. The engine has never been opened and I am the one who ran the compression check so those numbers are correct. Each cylinder held its number for about 1-1/2 minutes until I terminated the test. I think the "H" series had different heads which increased the ratio but I didn't think it was in the 10 range. I think one time I may have added a half can of Sea Foam to the oil and ran it for 50 miles or so before I changed the oil. When I pulled the covers to replace the stem seals, there was no sludge present. I did find a broken spring on #6 but I can't recall if it was intake or exhaust.

 

[DoubleDingo]

The truck was purchased new by a construction company for the owners dad to run errands and check on the field crews from time to time. It was also used as a spare while other company trucks were being serviced or repaired. I went to work for the company in February 1992 and have most of the paper work for the truck. When the truck was paid off (36 months) the owner transferred the title to his dad and the odometer showed 10.7k at the time. His dad passed in 1988 and about a year later, the truck went to our Austin office and eventually ended up at the owners ranch. It later came back to Conroe and was parked outside in our yard in 2005 where it sat until 2018 when the title was transferred to me. The engine has never been opened and I am the one who ran the compression check so those numbers are correct. Each cylinder held its number for about 1-1/2 minutes until I terminated the test. I think the "H" series had different heads which increased the ratio but I didn't think it was in the 10 range. I think one time I may have added a half can of Sea Foam to the oil and ran it for 50 miles or so before I changed the oil. When I pulled the covers to replace the stem seals, there was no sludge present. I did find a broken spring on #6 but I can't recall if it was intake or exhaust.

I knew it was something like that. Glad you got it instead of it going to the crusher or to somebody that wouldn't care for it like you have.

 

[Ricko1966]

1 quart per 2000 miles used to be considered acceptable by GM standards. Also engines were borderline worn out by 100k . Check the pcv hose,filter,and valve. Take a vacuum reading at the dipstick tube. Plug all valve cover openings put a vacuum gauge on the dipstick tube. If you are pulling a vacc at the dipstick tube,you are probably sucking oil into the intake. Malfunctioning pcv affects ring seal and crankcase pressure. Rings seal better under vacuum than under pressure, the pcv valve creates a vacuum in the crancase.If it's plugged pressure is created.

 

[texasmike]

Thanks Rick, I will give that a shot. I replaced the pcv valve when I started this project but with the quality of parts these days, one never knows. I'm thankful to hear from some of you older guys, not to take anything away from the younger ones. I'm referring to when you joined the forum.

 

[Ricko1966]

Thanks Rick, I will give that a shot. I replaced the pcv valve when I started this project but with the quality of parts these days, one never knows. I'm thankful to hear from some of you older guys, not to take anything away from the younger ones. I'm referring to when you joined the forum.

Make sure the hoses and filter are good and not plugged as well as the port at the carbureator isn't plugged.

 

[mtbadbob]

Make sure the hoses and filter are good and not plugged as well as the port at the carbureator isn't plugged.

Rick, this is your 6th grade spelling teacher reaching out...There is no "e" in "Carburator"...You're welcome!

 

[Ricko1966]

Rick, this is your 6th grade spelling teacher reaching out...There is no "e" in "Carburator"...You're welcome!

I blame my phone by the time I get carb typed,look what it says. I just click it. Ijust assumed the phone knew. I obviously didn't.

You must be registered for see images attach

 

[Terlingueno]

Rick, this is your 6th grade spelling teacher reaching out...There is no "e" in "Carburator"...You're welcome!

Actually there is no "A" in there


But then again, there are carburettors and perhaps carburetters...


...and then we have the classic, carburetor

 

[DoubleDingo]

Rick, this is your 6th grade spelling teacher reaching out...There is no "e" in "Carburator"...You're welcome!

Ahem...
Carburetor...

 

[mtbadbob]

I blame my phone by the time I get carb typed,look what it says. I just click it. Ijust assumed the phone knew. I obviously didn't.

You must be registered for see images attach

What do you expect when a 9 year old chinese kid programs them??

 

[mtbadbob]

Ahem...
Carburetor...

I guess I'll be getting a call from my 6th grade spelling teacher! I just knew the two vowels together weren't right! Hahaha!

 

[Grit dog]

Rick, this is your 6th grade spelling teacher reaching out...There is no "e" in "Carburator"...You're welcome!

Wrong