PDA

View Full Version : Aluminum Heads/ BG Injector Cleaner



Sean Malone
01-09-08, 05:27 PM
My wife and daughter took our truck up to VA a month ago to get the family piano that her mom didn’t want anymore. I had my mechanic do an oil change, change the front and rear end diff fluid to synthetic and give it a once over since I wasn’t going on the trip, I wanted to make sure the truck was in tip top shape for them. I also had them clean the throttle body because it stalled at a light a few times recently which is very strange. When I looked at the TB it looked pretty black. I had the dealer do this a few years ago and it ran like the day it was made afterward. They physically removed the TB and hand cleaned it. I learned afterward that my mechanic in FL used a BG injector cleaner on it.

My truck had a faulty thermo cause an overheat while my wife was driving it on the highway. She said she pulled over pretty quick once she saw some wisps of smoke and noticed the temp gauge (or 'gage' as GM and Dodge spell it) pegged.

My mechanic threw a new thermo in it and it still overheated. I took it back. He said it needs a new clutch fan (which surprised me because this truck has an electric fan and a belt drive clutch fan. The electric fan kicks in at around 235f. I would think if it was just a drive fan issue the electric fan would have been capable of keeping the truck relatively cool. I’ve read that some guys with my truck actually remove the clutch fan altogether and put a different electric fan that kicks in at 190). He put a new clutch fan on and he changed the plugs because he said there was coolant all over them (which piqued my interest because this truck as individual coil packs on each plug. If they fouled due to coolant that could mean a head gasket had blown.

I didn't drive the truck for four or five days after getting it back from the shop. (I really only use it to tow my boat around) and when I started it up it blew pure white smoke for about 5 minutes and ran rough at idle. It was fine once it warmed up and I was out on the road. I drove it over to my mechanic and he test drove it and said “it’s fine”.
A week later I had it out and it over heated on me. I had my mechanic come and get it with his rollback. He called today to say…head gasket. Damn I’m good.

This truck has aluminum heads. My mechanic said that we let it overheat too much and that aluminum heads will warp much easier than iron heads. Ok. Makes sense. Is that a true statement though? I thought aluminum was also supposed to dissipate heat better than iron heads. I guess when you are talking about that much heat, it doesn’t matter.

I’ve also read quite a bit that people that have had the BG injector system cleaner done on their vehicles report that it actually made their vehicles run worse. Has anyone used this or heard anything?

Methanolandbrats
01-10-08, 12:17 AM
I don't know about the specific questions you asked, but you may have bigger problems if the oil was diluted with coolant and you drove it. :(

G.
01-10-08, 12:29 AM
I am NOT a mechanic.:gomer:

The story is, that AL heads warp more than steel heads. When pressed, peeps say that the AL heads expand at a Different rate than the iron blocks, which causes the gasket breach.

I thought that they mitigated this.

Andrew Longman
01-10-08, 05:44 AM
I think you may have a problem with your mechanic.

Mysterious overheating, white smoke, coolant on plugs all point to blown gasket. :shakehead

STD
01-10-08, 10:30 AM
Oh my.

Sean Malone
01-10-08, 10:54 AM
I think you may have a problem with your mechanic.

Mysterious overheating, white smoke, coolant on plugs all point to blown gasket. :shakehead

That is what my wife thinks but he's been my parents mechanic for 10 years and he's done OK work for us in the past (even though I usually have to take it back to them to have something buttoned up).

Spicoli
01-10-08, 12:11 PM
wouldn;t have that prollem with a Diesel jeTTa

Andrew Longman
01-10-08, 02:15 PM
I am NOT a mechanic.:gomer:

The story is, that AL heads warp more than steel heads. When pressed, peeps say that the AL heads expand at a Different rate than the iron blocks, which causes the gasket breach.

I thought that they mitigated this.

That was the problem with the Vega.

I think the problem here is it normally would be mitigated but when the thermostat first broke the engine got enough hotter than normal that the head expanded much more than normal and breached the gasket.

But if it had been me and I knew the circumstances around finding out the thermostat failed, I would have pressure tested the system after replacing the stat and certainly after finding coolant on the plugs.

G.
01-10-08, 02:46 PM
after finding coolant on the plugs.Again, not a mechanic, but finding coolant on the plugs isn't very subtle, IT'S A BIG RED FLAG!

I mean, how else could coolant get into the cylinders? Head gasket, or rifle shot.

chop456
01-10-08, 03:11 PM
I mean, how else could coolant get into the cylinders? Head gasket, or rifle shot.

Wife putting coolant in the gas tank? :D

G.
01-10-08, 03:16 PM
Wife putting coolant in the gas tank? :D

which would be followed with a rifle shot...

You slow today?:p

(got storm damage?)

RacinM3
01-11-08, 02:50 AM
$5 says your head is either warped or cracked. If they do a head gasket make sure they resurface/mill the head back to true and pressure check for cracks. It is not unheard of for a head to be bolted back on and have it immediately overheat again due to failure to check it properly when it's off the motor.

We replace the head bolts with head studs in our BMW race motors to try to alleviate this problem.

Regarding your temp gauge: todays gauges are seriously buffered. Have you ever noticed that the gauge is either cold, in the middle, or pegged when overheating? My car runs a coolant temp range when warmed up of over 30 degrees, as most do depending on conditions. Yet factory gauges are always in the middle. This is because mfrs. and the dealers don't want to deal with every anal customer who comes in when their gauge moves slightly. The negative is when that gauge is pegged, it's too late - you're already overheated.

chop456
01-11-08, 03:05 AM
If they do a head gasket make sure they resurface/mill the head back to true and pressure check for cracks.

Excellent advice.

And G. - no damage here.

Sean Malone
01-11-08, 09:13 AM
$5 says your head is either warped or cracked. If they do a head gasket make sure they resurface/mill the head back to true and pressure check for cracks. It is not unheard of for a head to be bolted back on and have it immediately overheat again due to failure to check it properly when it's off the motor.

We replace the head bolts with head studs in our BMW race motors to try to alleviate this problem.

Regarding your temp gauge: todays gauges are seriously buffered. Have you ever noticed that the gauge is either cold, in the middle, or pegged when overheating? My car runs a coolant temp range when warmed up of over 30 degrees, as most do depending on conditions. Yet factory gauges are always in the middle. This is because mfrs. and the dealers don't want to deal with every anal customer who comes in when their gauge moves slightly. The negative is when that gauge is pegged, it's too late - you're already overheated.

I verified with him that he is sending out to the local machine shop to be remilled. He's doing both heads (it's a V8), which I thought was a bit weird but since I have this under warranty it's not going to cost me anything out of pocket.

I know what you mean about the temp gauges. My truck is kinda funny in that an idiot light comes on that says "check gauges" when the temp gauge gets up to the second hash mark. So what is the point of the gauge! :)

I don't know if they still do but GM actually put accurate temp gauges in their vehicles as recently as a few years ago. They still might.