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-   -   merlin572 keeps poppin dipstick out (https://67-72chevytrucks.com/vboard/showthread.php?t=367776)

merlinman572 10-18-2009 11:21 AM

merlin572 keeps poppin dipstick out
 
hi i have a merlin 572 in my twin cab c30 1977 pickup i use this on street and strip its running 13.008 @103mph quarter mile and still all steel problem i have is now and again dipstick blows out but compression tested and all seems good and cant feel any pressure by putting finger over end any suggestions most welcome merlinman 572 from the uk pics can be seen on youtube under merlinman572 cheers :devil:

77nomad 10-18-2009 11:55 AM

Re: merlin572 keeps poppin dipstick out
 
I seen a pic of an old '69 Camaro Trans Am Racer in Chevy Hi Performance where the guy drilled maybe an .080" hole in the end of a stock dipstick and then another in the bracket that mounts the tube itself. He then ran a spring beween the two. Simular to a throttle return spring. Another thing you cold do is run a crankcase evac system like the ones from moroso. Basicly a breather in the valve cover with a tube that runs down to a bung in the header collecter. I'm not sure the can be run with mufflers or not. Anyway I'll look for that pic.

77nomad 10-18-2009 01:59 PM

Re: merlin572 keeps poppin dipstick out
 
http://i1011.photobucket.com/albums/...d/100_1847.jpg My scanner is down this is the best I could do.

merlinman572 10-18-2009 02:14 PM

Re: merlin572 keeps poppin dipstick out
 
thanks for the tip thought about installing a t section into dipstick housing then hose upto oil catch tank

james colbert 10-19-2009 09:45 PM

Re: merlin572 keeps poppin dipstick out
 
Do you have a good valve crank case vent? There is pressure comming from somewhere

Rodms 10-20-2009 01:44 AM

Re: merlin572 keeps poppin dipstick out
 
How much vacum? and the crank case pressure could need a evac system to pull some and releive pressure

Marv D 10-20-2009 08:42 PM

Re: merlin572 keeps poppin dipstick out
 
Quote:

Originally Posted by james colbert (Post 3576019)
Do you have a good valve crank case vent? There is pressure comming from somewhere

DITTO!!! find why you have so much blowby and cure the problem, not the symptom.

EVBuilder 04-17-2010 04:13 PM

Re: merlin572 keeps poppin dipstick out
 
Early 1980's Ford AIR pump connected to valve cover is a cheap alternative to the expensive aftermarket vacuum pumps. Drawing a vacuum in the crankcase is worth a few extra horse power as well as saving gaskets and seals.

prostreetC-10 04-17-2010 04:24 PM

Re: merlin572 keeps poppin dipstick out
 
I can tell you if you are trying to run breathers in place of a PVC.....aint gunna work. I was told it would and now I have to pull the top of my tunnel ram off so I can drill/tap it to run a PVC line. If you think about it, besides a breather, there is really not anywhere else for that pressure to go. Clamp down that dipstick and something else is going to go. Seals won't win that battle.

cableguy0 04-17-2010 04:45 PM

Re: merlin572 keeps poppin dipstick out
 
Its needs a pcv. breathers arent meant to let air out. They are meant to filter incoming air to replace the air sucked out by the pcv

77nomad 04-17-2010 05:18 PM

Re: merlin572 keeps poppin dipstick out
 
Or maybe its the flux capacitior. That thread is a year and a half old.

regan wilson 04-17-2010 05:47 PM

Re: merlin572 keeps poppin dipstick out
 
The problem doesnt have be blowby . Crankcase windage can cuase it too . The last time I had a dipstick and had that problem I just put a vacuum cap with a hoseclamp on the tube and took it off when I wanted to check the oil.

nxtruck 04-18-2010 08:56 PM

Re: merlin572 keeps poppin dipstick out
 
Quote:

Originally Posted by regan wilson (Post 3925435)
The problem doesnt have be blowby . Crankcase windage can cuase it too . The last time I had a dipstick and had that problem I just put a vacuum cap with a hoseclamp on the tube and took it off when I wanted to check the oil.

Exactly. Windage can and will cause this to happen. I cured this problem on my 434 by plumbing a Moroso evac. system to the headers. Before I ran the evac, I had a small leak at the rear of the pan. But, after I hooked the evac. system up, no more leaks.

regan wilson 04-19-2010 07:09 AM

Re: merlin572 keeps poppin dipstick out
 
The only problem with that type of evac system is if you run mufflers you can end up with them full of oil . Ive seen some dripping oil before and of course smoking .

nxtruck 04-19-2010 11:25 PM

Re: merlin572 keeps poppin dipstick out
 
Yeah, I've seen that, too. My setup will pull right around 5" or so at 7000 or so. Just cruising around it barely pulls 1", but 1" is better than no vacuum and open breathers. I haven't had problems with oily mufflers.


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