No oil pressure | FerrariChat

No oil pressure

Discussion in 'Mondial' started by dennis_maine, Sep 5, 2017.

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  1. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    I have a 1981 Mondi 8, 2 valve. I just completed an engine out major. Adjusted valves, replaced front and rear crank and cam seals, replaced timing belts and idlers, resurfaced flywheel and replaced clutch. I put the engine back in, connected most things except the fuel injection, put oil in it, replaced the filter, and cranked it on the starter. I cranked for a total of around 2 minutes, and see nothing on the gauge. I pulled the lower oil cooler line off and see no sign of oil. Ditto the filter.

    What happened? I did remove the cams to do the valve adjustment because I don't have the tool to push the lifters down. Did I do something there? I marked the cams so I know they are in the right locations. I kept the bearing caps in order and replaced them in the correct locations. Did I block an oil passage when I replaced the cam cover gaskets? I just don't have any idea what happened. Any insights will be appreciated.
     
  2. 166&456

    166&456 Formula 3

    Jul 13, 2010
    1,723
    Amsterdam
    This problem is common after engine repair work in general, caused by an oil pump that is too dry so it cannot create enough vacuum to suck oil. Usually starting the engine (higher revs) or priming the pump with oil solves it. I don't have insight knowledge of the Mondial oil system to know where to inject oil if that is the case though.
     
  3. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    Well, thank you. I was thinking along those lines but didn't know if it could really happen that way. Maybe someone on here knows how to prime it, but I think I'll try pouring oil down the filter hole in the meanwhile.
     
  4. srephwed

    srephwed F1 Veteran
    Silver Subscribed

    Apr 29, 2012
    6,450
    street,md
    Full Name:
    fred brown
    Oil in the filter housing will make your day.
     
  5. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    ......Also take the plugs out, puts less load on the engine until pressure is achieved.
     
  6. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    Thank you to everyone. I'm off to Watkins Glen for the weekend but will try again next week!
     
  7. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    I just wanted to close this thread in the interest of completeness, and if anyone else has this issue, they will have some info. I pulled the oil pressure regulator assembly and squirted oil into the opening. That did the trick; I had oil pressure almost immediately.
     
    paulchua likes this.
  8. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,829
    Isle of man- uk
    Makes me wonder if the oil pump is getting a bit worn if you had to go down that road
     
  9. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    Good question, although the oil pressure has always been good, even at idle.
     
  10. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    12,661
    San Carlos, CA
    Full Name:
    Mitchell Le
    Next time, remove the oil connection of the oil line at the oil filter, fill that line up with oil, reattach it and spin it up.
     
  11. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,829
    Isle of man- uk
    These gear type oil pumps generally dont wear the gears but the bushes the gears run in can wear-this reduces the close Clearence between the gear teeth and the pump performance- as the pump generates pressure between the gear teeth, it has the effect of trying to push the teeth apart, but is resisted by the tight clearence in the bushes of the pump casing.

    If you get a repeat of no oil pressure, take the relief valve out and check it is clean and not sticking, check the spring length
     
  12. dennis_maine

    dennis_maine Karting

    Sep 11, 2007
    196
    ME
    Full Name:
    Dennis Haines
    Thanks to all for their kind assistance.
     
    paulchua likes this.

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