1988 suburban new owner
April 15th, 2019, 8:34 AM
#1
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1988 suburban new owner
hey guys I am the proud owner of a 1988 chevy suburban now and I could not be happier. it has the 350 tbi mated to the 700r4 trans and only has about 78k on the clock. I just wanted to ask you on a few issues I am having.
1.) smoke on startup, i'm assuming I have bad valve stem seals seeing as how after sitting for an hour or more will blow blue smoke on startup, my issue is that when totally cold I.E. first start of the day it blows blue smoke on startup and then continues to blow grey smoke for the first 3-5 mins of driving after which it clears up. I am not using any coolant from what I can tell and I had to replace the water pump and didn't see any unusual bubbling from the coolant while bleeding it so I don't suspect a head gasket. Can valve seals make it continue to burn oil for the first few mins of operation or am I looking at a different issue.
2.) warming up. I am simply unable to get the engine up to temp, the fan does shut off after throttling up a bit so I don't think its the fan clutch. I had it sitting for 30mins and the upper rad hose was just warm, not hot and the lower hose wasn't much hotter? it does have a new rad and water pump in it but i'm not sure why i cant seem to get it up to temp, after driving a bit the hottest the gauge shows is 120-140 deg. I replaced the temp sending unit since it was $4 and figured may as well try it but no difference. Are the 350 tbi's cold blooded or something?
those are the only two things stumping me, other issues it has
leaking rear main or valve cover gaskets,
leaking diff. pinion seal
broken trans pan bolts leading to leaking trans gasket
loose steering column
so I have my work cut out for me but I am curious as to the issues above because all I have owned before were GM H-bodies and ford products. Thanks!
1.) smoke on startup, i'm assuming I have bad valve stem seals seeing as how after sitting for an hour or more will blow blue smoke on startup, my issue is that when totally cold I.E. first start of the day it blows blue smoke on startup and then continues to blow grey smoke for the first 3-5 mins of driving after which it clears up. I am not using any coolant from what I can tell and I had to replace the water pump and didn't see any unusual bubbling from the coolant while bleeding it so I don't suspect a head gasket. Can valve seals make it continue to burn oil for the first few mins of operation or am I looking at a different issue.
2.) warming up. I am simply unable to get the engine up to temp, the fan does shut off after throttling up a bit so I don't think its the fan clutch. I had it sitting for 30mins and the upper rad hose was just warm, not hot and the lower hose wasn't much hotter? it does have a new rad and water pump in it but i'm not sure why i cant seem to get it up to temp, after driving a bit the hottest the gauge shows is 120-140 deg. I replaced the temp sending unit since it was $4 and figured may as well try it but no difference. Are the 350 tbi's cold blooded or something?
those are the only two things stumping me, other issues it has
leaking rear main or valve cover gaskets,
leaking diff. pinion seal
broken trans pan bolts leading to leaking trans gasket
loose steering column
so I have my work cut out for me but I am curious as to the issues above because all I have owned before were GM H-bodies and ford products. Thanks!
April 15th, 2019, 10:33 PM
#2
I'm here for the party
welcome from maryland.
a few things, sounds like you do have oil getting by the valve seals which ist too bad just make sure you have oil in the engine. second the black smoke is due to the engine running rich, which is due to the ecm dumping fuel till it see a certain temp. you have a temperature sensor and temperature switch. the sensor is in the intake next to the thermostat and is for the ecm and tells it how cold the engine is and how much fuel to dump. it should have a two wire plug on it. make sure it has a good connection and the wires arnt damaged.
the switch is in the drivers side head between cylinders 1 and 3 its for the gauge or light in the dash that will tell you what engine temp is at. it should have one wire to it, this only effect the gauge nothing to do with the ecm.
the cold temp almost sounds if the thermostat is stuck open or your system is cooling too much.
a few things, sounds like you do have oil getting by the valve seals which ist too bad just make sure you have oil in the engine. second the black smoke is due to the engine running rich, which is due to the ecm dumping fuel till it see a certain temp. you have a temperature sensor and temperature switch. the sensor is in the intake next to the thermostat and is for the ecm and tells it how cold the engine is and how much fuel to dump. it should have a two wire plug on it. make sure it has a good connection and the wires arnt damaged.
the switch is in the drivers side head between cylinders 1 and 3 its for the gauge or light in the dash that will tell you what engine temp is at. it should have one wire to it, this only effect the gauge nothing to do with the ecm.
the cold temp almost sounds if the thermostat is stuck open or your system is cooling too much.
April 16th, 2019, 8:43 AM
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welcome from maryland.
a few things, sounds like you do have oil getting by the valve seals which ist too bad just make sure you have oil in the engine. second the black smoke is due to the engine running rich, which is due to the ecm dumping fuel till it see a certain temp. you have a temperature sensor and temperature switch. the sensor is in the intake next to the thermostat and is for the ecm and tells it how cold the engine is and how much fuel to dump. it should have a two wire plug on it. make sure it has a good connection and the wires arnt damaged.
the switch is in the drivers side head between cylinders 1 and 3 its for the gauge or light in the dash that will tell you what engine temp is at. it should have one wire to it, this only effect the gauge nothing to do with the ecm.
the cold temp almost sounds if the thermostat is stuck open or your system is cooling too much.
a few things, sounds like you do have oil getting by the valve seals which ist too bad just make sure you have oil in the engine. second the black smoke is due to the engine running rich, which is due to the ecm dumping fuel till it see a certain temp. you have a temperature sensor and temperature switch. the sensor is in the intake next to the thermostat and is for the ecm and tells it how cold the engine is and how much fuel to dump. it should have a two wire plug on it. make sure it has a good connection and the wires arnt damaged.
the switch is in the drivers side head between cylinders 1 and 3 its for the gauge or light in the dash that will tell you what engine temp is at. it should have one wire to it, this only effect the gauge nothing to do with the ecm.
the cold temp almost sounds if the thermostat is stuck open or your system is cooling too much.