86.5 7MGE Problems

86.5 7MGE · 09-30-2009, 05:57 PM

OK, so I'm starting to think that I have a BHG. My symptoms include...radiator fluid spraying out constantly from the purge port on the reserve and when I drive sometimes not all the time it will start hesitating while the accelarator is pressed. It seems that I have to fill up the radiator every two days or so because of all of the fluid being purged out. I had Pepboys do a pressure check on my coolant system and they said it was my radiator cap at fault. So, I replaced all of my coolant hoses and vaccum lines to include the radiator cap and thermostat...is there something else that I can try that I'm missing before I assume that it's a BHG??? I still seem to have great power and only powerloss when my radiator gets low on coolant or it starts to hesitate.

At the same time I see traces of black smoke on my rear bumper and I know that white steam/smoke is a sign of a BHG due to coolant mixing in the combustion chambers. Could this be also from worn out piston rings?

Bill UK · 09-30-2009, 08:32 PM

If it’s any consolation I had a 1986.5 from new and managed to clock up 250.000 miles with the original engine, ok a few BHG`s on the way and a puff of black smoke now and again. The radiator should suck up the coolant from the expansion tank when left over night, so there should be no need to top up the radiator unless the expansion tank is so full and overflows and looses coolant. In my experience the temperature gauge only reads high when it just about to run out of coolant or the water pump has packed up (mainly due to the impellors worn out) I would check the water pump and the condition of the radiator.

86.5 7MGE · 09-30-2009, 08:53 PM

Ok Bill thanks for the imput I'll check on that. I have 244,000 miles give or take on it but before then when I purchased it the guy I bought it from said that the engine has been rebuilt, but couldn't find the paperwork on it. But I do see a placard on the engine from where it has been rebuit. The radiator looks worn I'll post pics asap. But not too sure about the water pump. Is there a way to test the water pump to see if it's operational or not?

Bill UK · 09-30-2009, 09:36 PM

I've often wondered about that myself, removing the cap and looking into the rad doesn’t tell you much. I guess you need some method of measuring coolant flow through the system. The reason I mentioned the water pump is I got caught out once; I had the usual over flowing expansion tank bottle, gurgling behind the dash noise and over heating. Did a BHG repair and drove it for about 10 miles down the road, opened the hood to find coolant overflowing from the expansion tank bottle. To cut a long story short, I removed the water pump to find the impellors had disintegrated due to the acidic condition of the coolant from previous BHG over the years. Combustion gases mixed with the coolant will start etching the metal parts such as water pump impellors. As you can imagine I'm a bit paranoid about water pump corrosion now.

86.5 7MGE · 09-30-2009, 09:47 PM

Wow, I actually hear gurgling behind the dash when I start my car after it has set for a while. The overflow tank stays full to the brim and doesn't suck back into the radiator like you stated it's suppose to. It just purges as I drive. Oh yea I forgot to mention that when I went in to change out the thermostat it was placed in backwards. Do you think that would have caused even more chances of water pump failure?

86.5 7MGE · 10-01-2009, 04:47 AM

Here are some pics that I took today of my expansion tank, radiator, and water pump.

86.5 7MGE · 10-01-2009, 04:50 AM

And some more...

86.5 7MGE · 10-01-2009, 03:49 PM

OK so this morning I when to check out my radiator again and to my surprise for the first time the radiator sucked up the coolant from the expansion tank it wasn't filled to the brim like it has been all week. So I start looking around and notice a drip coming from a hose above my water pump. Could this be the culpert or is it in combination with a faulty water pump?

btwilson86 · 10-02-2009, 03:13 AM

Any leak in the cooling system will result in it not easily sucking the coolant back from the reservoir. As the coolant cools down, the pressure drops which creates a vacuum in the system. This is what draws the coolant back in. If there is a leak, the cooling system could draw in air (which is easier for it to do) instead of that coolant, leaving it all in the reservoir

86.5 7MGE · 10-02-2009, 03:43 AM

Quote:

Originally Posted by btwilson86

Any leak in the cooling system will result in it not easily sucking the coolant back from the reservoir. As the coolant cools down, the pressure drops which creates a vacuum in the system. This is what draws the coolant back in. If there is a leak, the cooling system could draw in air (which is easier for it to do) instead of that coolant, leaving it all in the reservoir

Ok thanks btwilson86, I did find that there are two hoses that are adjacent to the water pump are swollen. I purchased a brand new water pump today just in case and it was the last one that they had in Denver out of all of their stores; and I'm going to change out the two hoses and see how that works. Would you change out the water pump just to be safe? I don't have any idea of all the parts on the engine; if I had all the money I needed I would replace everything with new parts just to save the headache for at least another 22yrs...lol

09-30-2009, 05:57 PM	#1
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	86.5 7MGE Problems OK, so I'm starting to think that I have a BHG. My symptoms include...radiator fluid spraying out constantly from the purge port on the reserve and when I drive sometimes not all the time it will start hesitating while the accelarator is pressed. It seems that I have to fill up the radiator every two days or so because of all of the fluid being purged out. I had Pepboys do a pressure check on my coolant system and they said it was my radiator cap at fault. So, I replaced all of my coolant hoses and vaccum lines to include the radiator cap and thermostat...is there something else that I can try that I'm missing before I assume that it's a BHG??? I still seem to have great power and only powerloss when my radiator gets low on coolant or it starts to hesitate. At the same time I see traces of black smoke on my rear bumper and I know that white steam/smoke is a sign of a BHG due to coolant mixing in the combustion chambers. Could this be also from worn out piston rings? __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust Last edited by 86.5 7MGE; 09-30-2009 at 06:01 PM.

09-30-2009, 08:53 PM	#3
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Ok Bill thanks for the imput I'll check on that. I have 244,000 miles give or take on it but before then when I purchased it the guy I bought it from said that the engine has been rebuilt, but couldn't find the paperwork on it. But I do see a placard on the engine from where it has been rebuit. The radiator looks worn I'll post pics asap. But not too sure about the water pump. Is there a way to test the water pump to see if it's operational or not? __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

09-30-2009, 09:47 PM	#5
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Wow, I actually hear gurgling behind the dash when I start my car after it has set for a while. The overflow tank stays full to the brim and doesn't suck back into the radiator like you stated it's suppose to. It just purges as I drive. Oh yea I forgot to mention that when I went in to change out the thermostat it was placed in backwards. Do you think that would have caused even more chances of water pump failure? __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust Last edited by 86.5 7MGE; 09-30-2009 at 10:09 PM.

10-01-2009, 04:47 AM	#6
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Here are some pics that I took today of my expansion tank, radiator, and water pump. Attached Thumbnails __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

10-01-2009, 04:50 AM	#7
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	And some more... Attached Thumbnails __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

09-30-2009, 08:32 PM	#2
Bill UK AEM EMS Join Date: Jul 2006 Location: UK Posts: 891	If it’s any consolation I had a 1986.5 from new and managed to clock up 250.000 miles with the original engine, ok a few BHG`s on the way and a puff of black smoke now and again. The radiator should suck up the coolant from the expansion tank when left over night, so there should be no need to top up the radiator unless the expansion tank is so full and overflows and looses coolant. In my experience the temperature gauge only reads high when it just about to run out of coolant or the water pump has packed up (mainly due to the impellors worn out) I would check the water pump and the condition of the radiator.

09-30-2009, 09:36 PM	#4
Bill UK AEM EMS Join Date: Jul 2006 Location: UK Posts: 891	I've often wondered about that myself, removing the cap and looking into the rad doesn’t tell you much. I guess you need some method of measuring coolant flow through the system. The reason I mentioned the water pump is I got caught out once; I had the usual over flowing expansion tank bottle, gurgling behind the dash noise and over heating. Did a BHG repair and drove it for about 10 miles down the road, opened the hood to find coolant overflowing from the expansion tank bottle. To cut a long story short, I removed the water pump to find the impellors had disintegrated due to the acidic condition of the coolant from previous BHG over the years. Combustion gases mixed with the coolant will start etching the metal parts such as water pump impellors. As you can imagine I'm a bit paranoid about water pump corrosion now.

10-01-2009, 03:49 PM	#8
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	OK so this morning I when to check out my radiator again and to my surprise for the first time the radiator sucked up the coolant from the expansion tank it wasn't filled to the brim like it has been all week. So I start looking around and notice a drip coming from a hose above my water pump. Could this be the culpert or is it in combination with a faulty water pump? Attached Thumbnails __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

10-02-2009, 03:13 AM	#9
btwilson86 Super Moderator Join Date: May 2007 Location: Billings, Montana Posts: 1,034	Any leak in the cooling system will result in it not easily sucking the coolant back from the reservoir. As the coolant cools down, the pressure drops which creates a vacuum in the system. This is what draws the coolant back in. If there is a leak, the cooling system could draw in air (which is easier for it to do) instead of that coolant, leaving it all in the reservoir __________________ 1989 7MGTE R154 Targa Top White Package w/Blue Interior Driftmotion 57trim CT26, Upgraded Intercooler, 2.25" Hard Pipes, 3" Turbo Back Exhaust with Test Pipe, HKS VPC w/GM 3 bar MAP sensor, APEXi S-AFC, Walbro 255lph fuel pump, ProSport EVO Series Boost / Fuel Pressure / AFR gauges, Lotek a Pillar Gauge Pod, HKS Type 0 Turbo Timer, Eibach Lowering Springs, Tokico Illumina II TEMS struts, custom powder coated Motegi Racing TrakLite wheels

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