Oil reccomendation to help with blowby.

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EvlFaust

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Hello;

My 1987 Bronco's 351w has a pretty substantial blowby issue. I'm getting pretty irritated with the amount of condensation and oil coming out of breather. I understand that it needs a ring job, but that isn't realistic at the moment. I live in Las Vegas so temperature ranges from moderate to high. I am wondering what weight oil would be recommended to help with the blowby until I am able to do a rebuild.

Thanks!

 

Rons beast

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Hey EF,

If the PVC valve is clogged or the hose to it is colapsed or broken you will get alot of blowby.

If the rings are bad you will be blowing bluish/gray smoke out the exhaust, as your run down the road. Bluish smoke only when you are excelerating = worn valve seals and/or guides.

If your sure it's rings, I have had limited success with Risolone engine treatment. and 20W50 oil. It didn't stop the smoke completely but did cut it down.

good Luck

 

miesk5

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yo EvlFaust,

As Bob & Ron Advised;

Inspect PCV Valve, hose & grommet; replace if neessary.

The positive crankcase ventilation (PCV) system cycles crankcase gases back through the engine (6007) where they are burned. The positive crankcase ventilation valve (PCV valve) (6A666) regulates the amount of ventilation air and blow-by fuel vapor to the intake manifold (9424) and prevents backfire from traveling into the crankcase. The positive crankcase ventilation valve is mounted in a vertical position.

96 PCV Air Flow Diagram.gif

CAUTION: Do not remove the PCV system from the engine. Operating engine without PCV system will reduce both fuel economy and engine ventilation. This will weaken engine performance and shorten life.

Info & pic, 1 port vs. 2 port for 5.0; "...That's a genuine Ford PCV valve. It's stock two port top (top of pic); makes it difficult to fit under the upper intake on an EFI 5.0 engine. Buy an aftermarket single port(lower in pic) and use the top on the Ford PCV..." miesk5 Note, often the rubber cap on the top port pops off

img_0724.jpg

Source: by Sixlitre (Malcolm H, Eddie Bauer)

Temporary Blowby Work-Around; Keeps the oil out of the intake, and off the engine:

Crankcase Breather Jar pic in an 85; "...splice into the line between the PCV and the intake. in between add a jar with 2 holes on top. one is an inlet and the other is an outlet. on the inlet side add a tube with a screen on the end which will trap the oily fumes from the air. so now u have fresh air going into the intake..." Click Next to see more pics

Source: by Chris85xlt (Chris C ( Erika) at http://www.supermotors.net/clubs/superford/registry/media/114839

one pic for Example;

1070712_img.jpg

The Steeda Oil Separator can be used too; http://www.steeda.com/store/steeda-mustang-oil-separators.html

The Steeda oil separator plugs into the PCV hose between the PCV valve and the intake manifold and removes aerated oil from the re circulated air and collects it in a tube that can be drained and recycled.

Also consider doing this soon too;

PCV Vacuum Supply Hose Rerouting in 87-93 5.0 Bronco, F Series & vans; MIESK5 NOTE; Include 5.8; Failure of the #8 piston or the #8 rod or rod bearing; "...Failure of the #8 piston or the #8 rod or rod bearing in Ford 5.0L, V-8 gas engines. Solution: During engine installation, reroute the PCV valve vacuum supply hose. Follow these steps: Plug the 3/8" (pipe) thread hole in the rear of the plenum where the PCV valve hose is connected. Drill and tap a 3/8" pipe thread hole in the center of the plenum and thread the PCV connector into it. Reconnect the PCV valve vacuum supply hose to the new location. Be sure the drain hole in the baffle is open. The baffle is under the PCV location in the valve cover. Installers who have rerouted the PCV system and opened the baffle drain hole have not reported any #8 cylinder failures..." http://web.archive.org/web/20061025155759/http://www.fourstarengines.com/techtips3.htm

Vacuum Supply Hose Rerouting in 85-93 Bronco, F Series & vans; Failure of the #8 piston or the #8 rod or rod bearing with 5.0L and 5.8L engines. Failure of the rear piston, rod, or rod bearing (cylinders 5 & 8). After discussing the situation with several installers, the problem has been narrowed down to the PCV system. This picks up crankcase gasses from above the #8 cylinder and dumps into the back of the intake. Miesk5 NOTE; I Don't know where Ryan got the year range (should be 87-93) because 94-96 Ford re-located vacuum port to the center, driver's side of the intake manifold; and where #5 cylinder info from.. most likely is a typo; read more

Source: by Ryan M (Fireguy50) at http://oldfuelinjection.com/files/Reroute_PVC.pdf

Remember that Only the vacuum supply hose is bing relocated and Not the PCV Valve.

Source: by fourstarengines.com via web.archive.org

Overview for late night reading;

Several failures are common in the PCV system; the most-often noticed is oil contamination in the intake &/or the air filter housing. Oil in the intake generally indicates that the oil separator has become restricted, which might be caused by gelling of the oil from moisture buildup due to insufficient PCV flow because the valve hasn't been changed on-schedule. But infrequent oil changes or overheating, or any combination of these conditions can contribute to oil in the intake. Oil in the air filter housing is almost exclusively caused by reverse-flow in the fresh-air tube, which is often the result of worn/stuck rings, hardened exhaust valve stem seals, or a ruptured head gasket. But it may also result from low-quality oil, incorrect viscosity oil, or excessive oil. An often-overlooked failure in the PCV system is cracking of the hoses, resulting in vacuum leaks & contamination of the engine oil. All vulcanized rubber (tires, hoses, bushings, etc.) ages & deteriorates, so it must be replaced as needed.

 

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