by spencerforhire » Fri Aug 10, 2012 6:52 pm
Vega motor- take 2; Tuesday night when I had it running I THOUGHT everything was OK. Wednesday morning I pulled the dipstick to see if I needed to top up the oil and I was greeted by what appeared to be a blueberry milkshake! 7 quarts of Royal Purple mixed with an unknown quantity of water. AAARRRGGGHHH!
Some investigation with a cooling system pressure tester and a set of leak down gauges turned up a problem in the center 2 cylinders on the right side(4 & 6). After teardown I discovered some interesting things;
1- the heads had previously been on a 400 and as a result had 6 steam holes drilled into them. Also 1 of the holes had experienced some significant heat and had "sagged" leaving a depression around it.
2- The heads had also been O-ringed in a previous lifetime, and a "clean-up" head plane job didn't remove all of the groove, especially around the 2 center chambers.
3- The Fel-Pro 1004(teflon coated reusable) head gaskets that were previously on the motor had done an admirable job of sealing up the mess from 1 and 2 above. I installed Fel-Pro 1003's(what AFR recommends for my heads); this turned out to be my undoing. They don't have a perfectly round opening around the chamber and didn't seal properly to the head in the area that was compromised by 1 and 2 above.
These 3 things all joined together and kicked me in the a$$.
The solution? Fill in the steam holes and remnants of the o-ring grooves with some J-B Weld "liquid aluminum", dig the old head gasket out of the garbage can(Wednesday was garbage day!) and re-assemble the motor with fingers crossed and bump the head nut torque from 75 up to 80 ft/lbs(ARP says it's OK). Everything is all good; no more water in the oil and no more bubbles in the rad. This winter I need to get the heads planed a whole bunch, but for now it'll do.
I am officially sick of wrenching on this thing; I'm taking the rest of the weekend off.
The "fleet"-
72 Vega HB Drag Car -383/'Glide/9"(9.35@146.19)(5.94@117.28 1/8th)
77 Vega Estate wagon- project(someday)will have TPI305/T-5, S-10 spindles/axles
76 Vega GT- 400/4spd/9" retired from active duty(rusty)
06 Silverado 2WD ex.cab daily
03 Silverado 2WD ex.cab (retired)
06 Haulin' 20ft enclosed car transporter
06 GMC Canyon Shop truck
07 Colorado project( 5.3 4L60e swap)
99 Saturn SL1- wife's car
01 Saturn SC2- son's project
07 Saturn Ion Redline project
and 4 more Saturn "parts cars"
Note- the very act of listing all of these has made me realize I have some kind of problem.....
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