Thread: Home Brew Penetrant Mix for a Seized Engines

Originally Posted by discorevy

Ah well, if it's a struggle to turn through 720 degrees, then, as you say, "off with it's head".

Hello Discorevy,

It is a Perkins six cylinder diesel motor with a 354 cubic inch capacity AKA 6354 or 6.354 or another one is 6-354. All variations seem to be in equally wide usage on the internet.

I have printed out the Tightening Sequence Figure E:13 found on page Cylinder Head-E.7. Year of publication - 1981. Whereas the really handy "Remove head" workshop manual was 'issued' in 1956. It seems that the exact match for my engine would be somewhere in between the 1981 one and the 1956 one. It seems that the 1981 Workshop Manual caters for a wide range of models and offers of compromise of less detail to cover commonalities within the range at the sake of detailed per model information. I did work out the engine I am working on year code from a number on the engine block. It is a 1978 year of manufacture. I would like to match the engine year of manufacture against a more specialist 1978 release workshop manual if I can. Hopefully it will be better that the 1956 edition level of instruction of just - 'remove head'! Although - the 1956 edition would not take much effort to beat

Kind regards
Lionel

Hello All,

Is rust still magnetic after it has been treated by molasses?

The reason I ask because I took the head off the 6354 Perkins diesel today - my "good" motor. Dispersed amongst the molasses diesel penetrant mix is some grit. I can feel the grit when I rub thumb and forefinger in the penetrant mix that has accumulated at the top of each piston. I thought if molasses treated rust is still magnetic I might be able to identify if the grit is sourced from metal rusting. Or the grit could be something else that has found its way into the engine.

I have had a feel and visually inspected down each cylinder bore and not found any prominent rings, ridges or vertical scours around or down the bores. I will soak up the remaining penetrant mix and the thoroughly clean the bores and shine a torch down them before I get too excited about the bores still being in good condition.

The other thing I am contemplating is taking one of the original CAV - as in authentic CAV - not a clone, starter motor to the auto electricians and getting it rebuilt. Prior to my taking the head off the only thing that would stop me from consecutively turning the engine through 360 degrees with the metre long bar was my available energy. After multiple full rotations of the motor I would hook a battery up and crank the new 'high torque' starter motor and it might either shudder in place or turn the fly wheel about 10 degrees.

Was the motor seized when I started working on it a couple of months ago? Yes it was! I could put a metre long bar that had was positioned between two flywheel bolts and I could hang off the end of the lever with my full body weight behind it. I could bounce off the end of the bar and nothing moved. The motor required being soaked in penetrant for a couple of months and then some very light friendly persuasion with a lump hammer striking the end of a metre long metal bar before the engine started to move.

I will take the head off the Perkins 6354 which I bought knowing that the motor is seized without swinging off the end of a lever which is fixed between two flywheel bolts.

Kind regards
Lionel

Hello All,

I am starting to wonder if there is a point between a motor having good compression and a brand new starter motor possibly having a feeble ability to turn a flywheel around? Where the ability of the new 'high torque' clone to turn the flywheel means the engine itself may in the big scheme of things have too low a compression.

I did not start and run the motor immediately after I bought it home. I could have done a compression test on it then. Instead the motor sat for two years in a shipping container and then ceased to rotate.

With the head off I may as well keep going with dismantling the motor and taking the pistons out. Getting the bores honed and making sure the piston and rings are serviceable. Measuring all the clearances and tolerances to confirm they are all in specification.

It would be good to have an original as per the engine's era of manufacture and the engineers selecting a particular model of starter motor. A CAV starter motor. Once the old CAV is rebuilt I will trial the new clone starter motor first and then compare the ability to turn the flywheel against the rebuilt CAV starter motor's ability. Plus do a compression test on the motor.

At least with everything pulled down now, it can be tested and reassembled. This should allow me to have confidence in the motor. If I had managed to get the motor running couple of months ago, whatever the grit is down the bores would have shortened the motor's operational life. Plus, overall new lessons will have been learnt and hopefully greater levels of both competence and confidence gained. For example, buy motor, get motor home, get motor started. Do a compression test. No ... I will revise that ...

How about .... get motor started and do a compression test Before paying for the motor and bringing it home. Now, that would be a totally novel experience for me!

Kind regards
Lionel

Lionel, why not ask the question on the old truck forum, there is much Perkadyne knowledge on there. You may also get the book you're after.
At least one person will have the correct edition, who could copy the relivant section, to reassemble your engine.

Hello All,

There are still some things that bug me about the 'good' Perkins motor. I was shown a video of the motor running before I travelled to the seller's location to pick the motor up. It took a couple of weeks before I could arrange time off work.

When I picked the motor up it did not have a starter motor fitted to it. It did not have a flywheel fitted to it. There was no water pump or fan fitted to it - all of these parts were shown in the video. When I commented that the parts were missing these parts were rapidly sourced from various piles of parts they had in the yard.

It would have taken time to refit these parts and I needed to travel a couple of hours to do a second pick-up of parts. So, the opportunity to get the engine running was not available to me at the time. Now, if a buyer makes the stipulation that they want to purchase a running motor why take all the parts off that allow the motor to run before it is picked up?

The video did not show the engine number either. I suppose it all boils down to Caveat emptor “let the buyer beware”. Also, a fair degree of gullibility on my part at the time too. Just too many questions at the moment about the motor.

Oh well - the motor will soon be a 100 percent known factor - for the better ... fingers crossed!

Kind regards
Lionel