51 V8 tappet noise

[impac]

I just purchased a 15 Lincoln Cosmopolitan Convertible from a Museum. It sat for years. After some work get it started. There is a loud tappit noise. Any ideas what it is? Value adjustment? If so, how without a rebuild??  

[19tom40]

That is a beautiful and rare car. The Road Race Lincoln Register and the Lincoln Continental Owners Club have members that own Cosmopolitans.

 

If your car still has the original Lincoln engine, it has hydraulic valve lifters.

 

The first try I would take is to add a quart can of Marvel Mystery Oil to the crankcase and drive it for 50 - 100 miles at speeds varying from 20-50mph. Drain the oil, replace the filter cartridge an refill the oil pan with a good grade of 10W-30 oil. If it just a stuck lifter it should be quiet now.

 

If the first try does not fix your problem, you are probably going to rebuild one or more lifters and you will need the Lincoln Mercury Overhaul Manual for instructions on how to accomplish that.

 

I have this version and there are other formats out there: http://www.then-now-auto.com/product/1949-1951-lincoln-mercury-overhaul-manual-2-volume-set/

 

Other versions:

https://www.amazon.com/1949-1951-Lincoln-Mercury-Overhaul-Repair-Reprint/dp/B00435JM0C

 

https://www.ebay.com/itm/266075891402?hash=item3df35be6ca:g:zCQAAOSww~JjuJhg

 

There is a Lincoln forum here also. There is not much activity on the 1949 and later models, but I will try to help all I can.

Edited May 13, 2023 by 19tom40 (see edit history)

[impac]

Hi Tom,

 

Thanks for the info.....

 

I do believe it is #s matching, so yes hydraulic lifters. Others have said same as you, add 1 or 2 quarts of either ATF or Marvel Mystery oil and easy drive for 100 miles. One guy said could take up to 1,000 miles. I sure hope I don't have to take apart.

 

Currently the gas tank is being boiled. Once installed I'll drive her in hopes of solving the noise. Thanks for links if I will have to wrench. 

 

Below is a video of the engine running.

 

 

Thanks for your help!!

[19tom40]

I don't like to drive them more than 200 miles with that much MMO in the crankcase. It can loosen up chunks of sludge. Most of the time they clean up and quiet down in less than 50 miles. If it is not quiet by 100 miles, I would still drain and refill as you will loosen a lot of sludge that should be removed. Make sure that you drain it hot to ensure that the sludge remains in solution. Then I would just add 1 pint of MMO and drive it for 1,000 mile or until it becomes quiet. Make sure that every time you drive it, it gets up to operating temperature (about 15 minutes after the thermostats open). Do not let it idle for long periods as that will add to the sludge ( idling with a stuck lifter will let un-burned fuel elements collect causing sludge).

 

It seems to be idling fast in your video. Idle speed is 450RPM in drive.

[impac]

I am also going to remove oil pan and clean, then drive the 100 miles.

 

Questions:

 

Where and how do I check/fill brake fluid?

 

Where and how do I check/fill convertible top fluid??

 

Where is the oil coming from in picture, just under passenger door?

 

 

[19tom40]

The master cylinder filler opening is under the floor on the drivers side of the car. It should be about straight down from the brake pedal.

 

The top and window reservoir is at the bottom of the pump in the engine compartment. For photos got this topic:  https://forums.aaca.org/topic/266891-1949-baby-lincoln-hydraulic-pump-installation/#comment-1435870

 

That oil is probably rusty brake fluid from a leak in the line feeding the passenger window. It seem that the museum did not flush and fill the system as required in the owners manual and the moisture has corroded the lines. You probably will have to rebuild the window cylinders and replace the hydraulic lines for the windows and top.

 

If it was my car, I would replace the lines, flush the system with denatured alcohol and replace the brake fluid with a  hydraulic fluid. That would eliminate the annual flushing required with DOT3 brake fluid. Then you could see what works and have the parts that don't work rebuilt.

 

You are probably going to find the same situation with the brakes. There I would replace all lines and replace or rebuild all of the cylinders. The wheel cylinders are available from Rock Auto under 1951 Mercury. The master cylinder may be available elsewhere. All cylinders are the same as the 49-51 Mercury. Use DOT 3 or 4 and test or replace no further apart than 3 years. A seldom used system will accumulate water faster than a system used in daily driving.

 

I wish you all the luck in the world to get it back on the road where you and others can enjoy it. I suggest that you post any new topics in the Lincoln and Zephyr Forum. Other 49-51 Lincoln owners may read your post and be able to give you more insight that I can.

 

 

 

[impac]

@Tom,

 

Is the brake master cylinder accessed under carpet or under floor, bottom side?

 

The picture should i believe to be a break line going through the floor to under driver seat.

 

I will post in the Lincoln and Zephyr.

 

 

[billorn]

1 hour ago, impac said:

@Tom,

 

Is the brake master cylinder accessed under carpet or under floor, bottom side?

 

The picture should i believe to be a break line going through the floor to under driver seat.

 

I will post in the Lincoln and Zephyr.

 

 

I dont think thats a brake line. I believe thats a hydraulic line that feeds the power seat from the big pump under the hood. The same system should also power the power top and power windows (if equipped).

[impac]

Wow everything is hydraulic OMG 🙂

 

Still haven't figured out where to add brake fluid or hydraulic fluid to the top, ETC

[19tom40]

The opening for the master cylinder is under the carpet. The master cylinder is under the floor and the filler opening in accessed from inside the car.

 

Here is a photo of the pump for the windows, seat and top. The reservoir is the large aluminum colored pot held in place by the black wire. Be careful to support the pot when pushing the wire bail to remove the pot. If there is any fluid left in the pot, it will destroy any paint that it touches. For the first time, I would cover everything under and behind it with a plastic masking sheet.

 

[impac]

I found the floor access panel for the master brake cylinder. Fluid level was good though a bit discolored.

 

I also remove the hydraulic pot, it was empty. Since it was empty, probably a leak somewhere. Can I use AFT or stick with Dot3? How do I bleed the system? 

 

Thanks for your help!!!