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Discussion Starter · #1 ·
This sbc motor runs about 19" of vacuum when you start it in the morning.And it runs good till it gets warm.Then the vacuum drop down to 16.5" and far less in gear around 12".Also for some reason a lot of water comes out the drivers side pipe.And none at all on the other side..It's not just a little it's very noticeable,plus theres a little white smoke when its warm.Also when you press the brake the idle rpm goes up.So I was thinking the intake gaskets did'nt seal right.Im not sure any opinions?
 

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The vaccuum will drop as the idle drops. The idle is usually lower in gear than in park. Are you sure it's smoke coming from the tailpipe, could be steam which means a head gasket. Does it do this when the vehicle is warm or cold. Water is a byproduct of combustion, a little at first start is normal when the engine is cold. Should not do this when the engine is warm.
 

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Discussion Starter · #3 ·
the white smoke only comes out when the engine gets warm.And the vacuum drops when it's warm.The idle rpm goes up 200-300 rpm when you push the brake.Also the engine has no miles on it yet.
 

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if the motor has 0 miles then the rings are not seated.....the cylinders are not sealing to pull a vacuum.....so the vacuum readings you are getting can be wack-o.....get a couple of hundred miles on it before testing and tuning for Hg

cold motor=choke on=1200rpm idle=more vacuum (19 on a brand new build is ok)
warm motor=choke off=700rpms idle=less vacuum (16 and steady on a new motor as a start point to tune later is ok)
put it in gear=roughly 3" drop is pretty normal with a warm (broken in) motor (12 doesn't surprise me cause the rings aren't sealing yet)

won't hurt/might help, re-torque the intake

yeah, agree with xntrik.....take it to your engine builder for testing and help, especially the white smoke when warmed up....
 

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Discussion Starter · #6 ·
the machine shop put together the short block.I assembled the rest.Im just not sure why there's white smoke and water coming out one side.It's got true dual exaust with no h/X pipe.Im not sure because it only happens when the engine is warm.I was thinking it could be because the intake gasket did'nt seal right.Or a head gasket.Plus the rockers dont want to stay adjusted.Every once in awhile they will loosen.
 

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bonzi,
I'm saying ask the machine shop for guidance cause the list of questions of what you did or did not do is 30 minutes plus of discussion to identify the cause.....with the info so far....sounds like a coolant head gasket leak

here's just a few possible causes not in any particular order:
did you have the machine shop check the heads for warpage?
did you use new head bolts, if yes how many times did you re-torque them?
did you seal the head bolts threads?
were your hands really clean when you handled and installed the head gaskets?
did you clean the heads and block surface really clean with lacquer thinner or brake cleaner when you installed the head gaskets?
have you pulled the D side plugs and inspected if only one is wet (take your plugs with you to the machine shop)
have you retorqued every bolt on the motor?
did the machine shop deck the block and put a smooth correct finish for your particular head gaskets?
did you torque the head bolts in the correct sequence and TQ steps
is your torque wrench calibrated correct....been using it for a breaker bar?
did you follow every instruction exact in your "how to rebuild" book
is the radiator cap "puking" from steam pressure when you turn off the warmed up motor?

very very easy for anyone to make just one mistake and have it bite you in the butt at the end
 

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Discussion Starter · #9 ·
No heat riser,Did get new head bolts.I have'nt retorqued the head bolts/intake bolts.Im not sure about the radiator I didnt think about checking it.I will do these things and get back to you,Thanks again.
 

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Presure test the cooling system to see if it is leaking. If it is you MAY be able to determine where. You may want to pull the plugs and look for one that is real clean looking compared to the others. If you find one, this is your problem cylinder
 

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Discussion Starter · #12 ·
I retorqued the head bolts,and intake.And the engine did run a little better.I also drained the oil and filled it with oil.And ran it for 10-15minutes and did'nt have any more milkshake oil.I did'nt check the plugs.I will do that in the morning.I still have a little white smoke/water but a lot less than before I changed the oil.Is there anything else I should check while im at it?
 

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because the oil was a milk shake you have no option but to pull the motor, tear it down to the short block, and take everything to the engine shop for inspecting and testing

let them assemble the long block and give you a guarentee
 
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