diference 170 & 200 ?

[Anonymous]

whats the difernce from a 170 &200 ? is it just the stroke? are the rods the same size? or the pistons ? i took out a 170 from my boat put in a 200 when i turn it over it sounds like the rods are hitting the oil pan ??????????????? :x do i need to add an extra head gasket to it if i use the 170 head? man this is all a nitemare i wish i could pay someone to do all this stuff. that is just a thought help please .. the boat guy

 

[pedal2themetal45]

HI AND WELCOME TO THE BEST INLINE 6 BOARD
Sence you used the 170 head you may have valve train problems as well as compression.. Did the 200 run befor you changed the head? What year was the 200 and what year is the head, look over the sticky's on head swaps that may be of help.. maybe timming is off aswell it well make it sound like a can of rocks.
More info well help..
tim

 

[CZLN6]

Howdy All:

The 170 has a stroke of 2.94" and uses a flat-topped piston.

The 200 has a stroke of 3.126" and uses a dished piston.

The heads are interchangeable, but the later (after '70) have a larger volume chamber- 52 cc to 62 cc. A 170 head on a 200 should not have valve to piston clearance problems because of the dished pistons in the 200. It may suffer from too high compression depending on the thickness of the new head gasket.

Have you preset the valve clearances? is the noise from the top or bottom of the engine?

Adios, David

 

[Anonymous]

Yes the 200 run before I changed the head .the 200 is1975 and 170 is 1965 . I took off the head and it turns over but sounds like something is hitting . Maybe the rods to long for the marine oil pan ? the noise is in the bottom I have the 200 head they do look alike . and the 200 used flat top pistons as well as the 170 .

 

[pedal2themetal45]

I would check and see how deep is the marine pan compaired to the stock pan I can't imangen it being that much more stroke to hit the pan but sence you are using a different pan and head I would check it. maybe when you start it see if you can feel it hitting the pan or use a long screwdriver (it well act like a stehascope) and hole the handle to your ear and put the pointed end against the motor in various palces's and see if you can locate (iceolate) were the noise is comming from... Did you change anything else??
Tim

 

[CZLN6]

Howdy Back:

A stock, OEM, 200 from '75 will have dished pistons. Either it is not stock or ?

IF you are not using the stock 200 pan, you could be experiencing clearance issues in the pan. Make a visual comparison of the 200 pan and the one you are using. The radius increase in stroke between a 170 and a 200 is less than .100" or half of the increase in stroke. 3.126" - 2.94" = .186" / 2 = .093"

Are you sure the 170 is a 170 and not a 144? The 144s were a popular choice for inboard applications in the '60s. The 144 stroke is 2.5". If the pan was designed for economy of space, it could be too tight for a 200 stroke.

What a lovely adventure.

Adios, David

 

[Anonymous]

That’s a good idea did not think of that yet. I changed the cam. I used the one from 170 and put in the 200. think it is a 170 but I cant be for sure there are no stickers on it the numbers on the block start with C . ill check the depth of the oil pan . thanks ill post the info. As soon as I can …keith :roll:

 

[mugsy]

In "Fordspeak" (or their part numbering system) if the first letter is a "C" then it means it's a 1960's part. The second number is the year in that decade, so a "1" means 1961, "3" means 1963.. etc. Part and casting numbers that start with "D" means its a '70s part.... blah, blah, blah!

tanx,
Mugsy

 

[Anonymous]

well the oil pans are the same . that one good thing , im going to pull the engine back out tare it down and see what the deal is i will post as i go .

 

[pedal2themetal45]

I changed the cam. I used the one from 170 and put in the 200. …keith :roll:

Did you use the used cam from the 170 or did you put i a new one for the 170 :

You may have some probs with the old cam did you keep the same lifters on the same lobe they came off of?? They delevolp ware patterens so its Ok to use a old cam as long as you eather use new lifters or use the old ones on the same lobes of the came..
tim

 

[Anonymous]

yes i used the 170 cam and lifters in the 200 i have an old 1968 shop manual i used it as all the info. on how to set the timing install the cam ect....

 

[addo]

This is only a "maybe", but:

I recall seeing that Ford increased relief clearances on the cam for the rods, at the time of going to the 200. The distance from crank to cam is the same for 200s and 170s but the extra throw originally took the rods a little too close for comfort.

If you pulled the sump, it would be possible to see if the corners of your rod caps are contacting the cam. Hopefully, it's something else.

You are using the 1975 oil pump and distributor, etc? (Including the 5/16" hex oil pump drive shaft.)

Cheers, Adam.