What am I doing wrong again?
#1
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What am I doing wrong again?
On my Oldsmobile Achieva with the 3.1 in it has developed another oil leak from the driver side part on the lower intake right below the thermostat housing. I just redid the intake about a month or so ago to fix the same leak and I can't figure out why it has started to leak again about a month later. I followed all of the directions to the letter clear down to replacing the the lower intake bolts this time around. My maintenance manual said the lower intake bolts are suppose to be torqued down to 115 inch pounds on the vertical and diagonal bolts, 115 inch pounds is 9.5 foots pounds when I got that converted over by a inch pound to foot pound setup I found online. Also every time that I redid the intake I applied the 3MM thick bead of RTV on both of the mating surfaces along with using the good metal/rubber gaskets from Fel-Pro on the lower intake. So does this mean I could have a cracked lower intake or what since it started to leak oil again in the same spot.
#3
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Yes I applied the RTV before I sat the lower intake in place and torqued it to spec. Also I ran out of day light before I could finish it so it did sit overnight before I was able to finish it up the following morning.
#5
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I have decided to when it get a lot warmer I will dismantle the upper half again and take the lower intake to a machine shop and have them check it for cracks along with checking to if it may be warped since my step dad redid it the first time and he overtightened the lower intake bolts along with cracking the upper intake I already replaced the upped intake awhile back but I will probably ask them to to see how much extra it may be for them to clean the inside of the upper intake due to a lot of carbon build up. So I'm hoping that my step dad didn't wrap my lower intake but I will found out when it get warmer and I get it taken to a machine shop.
#6
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Also I almost forgot to ask to see if this may be my problem instead of a leaking lower intake. I am wanting to know could my oil leak actually be coming from the cap looking thing by my thermostat housing. I think that is where the oil pump drive shaft is and I have never replaced that O-Ring either time I did the intake job and after some research I found that if that O-Ring fails it could make it look like the LIM is leaking oil. Is that true or not.
#7
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True Car Nut
no idea, seems reasonable. orings get hard and leak when old. i had a 2.8 for 230k, a 3.1 for 300k+ and a 3400 for 180. none ever leaked oil. only ever had problems with dexcrap eating stuff, like the metal crossover tube for the coolant
#8
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Ok. Mine had the dexcool in it but when I bought it I had it flushed out and converted to 50/50. Also at that time I replaced the thermostat, temp sensor and most of the hoses on the car. I am going to wait til it is warm and I am going to drain the cooling system and then pull the thermostat housing to look at oil leak and see if I am be able to put more RTV on it so I am hoping that this will work so I don't half to pull it back apart. Also I will replace that O-Ring why I'm in that area.
#9
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True Car Nut
what kind of rtv you using? i use permatex black recommended for high oil resistance
Gasket Makers : Permatex® Ultra Black® Maximum Oil Resistance RTV Silicone Gasket Maker
Gasket Makers : Permatex® Ultra Black® Maximum Oil Resistance RTV Silicone Gasket Maker
#10
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I used the black RTV that came with the new gaskets. I bought the from my local oreilly'*. here is the link to them. Fel-Pro MS98004T - Intake Manifold Gasket Set | O'Reilly Auto Parts