Losing oil in ti 350 - risks to continue driving it?

[kmehr]

Drove the old girl hunting yesterday, about 100 miles round trip. I am getting some blue smoke on start up, but it clears up pretty much right away. I filled up with super premium gas to see if it would help with the spark knock. Spark knock seemed to be reduced possibly but is definitely still there. When I pop the hood, there is definitely a lot of noticeable valve noise - "clatter"- from the valve covers. My theory is bad valve seals which are dumping oil in the cylinder and leading to the knock/carbon build ups- Thoughts?

 

[someotherguy]

RE: spark knock, I don't see anywhere that you have mentioned checking or setting the base timing. Engine fully warmed up so that it's at normal idle, disconnect tan/black wire which on your '89 you will find a disconnect for it hiding in the general area of the black plastic electrical center cover on passenger side firewall, use timing light to set for 0° BTDC, snug it back down and re-check before reconnecting wire. After reconnection timing should advance considerably, usually 12° or so, enough that you may not be able to see it on the marker unless you have a dialback style timing light.

If still pinging after setting base timing correctly, time to inspect vacuum and electrical connections for the EGR valve and test the valve. Let us know which kind it has; the regular negative backpressure type has a small solenoid on a bracket at the passenger side of the TBI, vacuum inlet at the front and output at the rear along with a smooth connection with nothing on it (vent; originally had a small foam filter almost always gone by now) - it's easy to test this setup if you have a hand vacuum pump like a Mityvac. If it's got the port EGR with the finned solenoid that's a different scenario and I'll have to look up some testing for you as I've pretty much never had to mess with those.

Also, confirm 100% the engine is not overheating as that will cause spark knock too.

Richard

 

[kmehr]

RE: spark knock, I don't see anywhere that you have mentioned checking or setting the base timing. Engine fully warmed up so that it's at normal idle, disconnect tan/black wire which on your '89 you will find a disconnect for it hiding in the general area of the black plastic electrical center cover on passenger side firewall, use timing light to set for 0° BTDC, snug it back down and re-check before reconnecting wire. After reconnection timing should advance considerably, usually 12° or so, enough that you may not be able to see it on the marker unless you have a dialback style timing light.

If still pinging after setting base timing correctly, time to inspect vacuum and electrical connections for the EGR valve and test the valve. Let us know which kind it has; the regular negative backpressure type has a small solenoid on a bracket at the passenger side of the TBI, vacuum inlet at the front and output at the rear along with a smooth connection with nothing on it (vent; originally had a small foam filter almost always gone by now) - it's easy to test this setup if you have a hand vacuum pump like a Mityvac. If it's got the port EGR with the finned solenoid that's a different scenario and I'll have to look up some testing for you as I've pretty much never had to mess with those.

Also, confirm 100% the engine is not overheating as that will cause spark knock too.

Richard

This is very helpful. I'm out of town all week so I'll have to try this stuff out next weekend. This may be a dumb question, but since my truck is a Cheyenne, I don't have an engine temp gauge- how do I tell if it's over hearing or not other than a check engine light?

 

[someotherguy]

No good trusting the gauge anyway, even if you had one. They very often read low.

Borrow an IR temp gun (non-contact thermometer, uses infrared) and aim it at the area of the intake directly below the thermostat housing. A "max reading while scanning" type is best, a feature many have - so you can see the hottest temp reading as you move around that immediate area. With the correct 195F thermostat you should get a reading very close to 195, with the engine fully warmed up. Anything more than 200 and you should be very concerned that there is an issue. Anything under 190 or so should have you looking at whether the correct thermostat is installed (or if there's one at all), it could be stuck open allowing unimpeded flow, or fan clutch is stuck engaged, etc.

Richard

 

[kmehr]

Been out of town all week so I haven't had a chance to actually do any work, but it did order new valve guide seals and went ahead and got new valve springs- they were $30 and I'm getting a lot of valve noise under the hood so I couldn't hurt. Got my timing light in the mail and a new harmonic balancer on the way as well.

Anyways- my cousin mentioned something to me- that all the oil burning is making its way to the cat and combusting in there, which is why it sounds like I have an exhaust rattle under the cab where the cat is. does this sound plausible? Also, any chance that I could have burned up my brand new cat in 2000 miles with my massive oil disappearance?

 

[TXVortec454]

Worry about one problem at a time. Replacing those valve seals should be priority number one. The reason your plugs aren't nasty is because you are likely loosing all your oil from the exhaust valves, thus not showing up on the plugs. Bad valve seals can dramatically increase oil consumption.

 

[kmehr]

Finally found some time, (and had nice weather) to work on the ole girl. Replaced the harmonic balancer (the rubber ring in the old one was rotted to hell) and the fuel filter. Seems to idle better already with the new filter. Supposed to be nice again tomorrow so I'm hoping to tackle the valve seals. I bought both intake and exhaust.

 

[vic_v8]

doing those seals should cut the oil consumption to about 1/2 of what you were using. Afterwards, Sea Foam it as stated before.

 

[kmehr]

Didn't get a chance to work on it today, hopefully this weekend will be nice weather. I did read in my factory service manual that when putting the rocker arms and everything back together, to adjust the valve lash, snug up the rocker arm nut to the point that the push rod stops spinning, then turn the nut 1 full turn. Most write ups I've read say 1/4 to a half turn after the push rod stops spinning freely- Thoughts?

 

[ChevyBoat]

I would go with factory service manual just my opinion