Winnebago motor home

[muddacres]

My MOM and Dad had this motor home when I was younger it had a 318 in it. The spark plugs wasn't angled they were strait in. Has anybody ever seen these type of heads and what where they.
Jim

 

[Old Geezzer]

I wonder if it wasn't a 413? They used them a lot in motor homes before they started using the 440..

 

[fishy68]

I wonder if it could have been an old Poly 318? It's been so many yrs since I saw one I can't remember how the plugs were on them but I know the heads are totally different from a LA 318.

Do you know what year the motorhome was?

 

[Old Geezzer]

Some where I may have a picture of one I had here ... Now the hunting starts:read2::read2:

 

[caferacerx]

I have one of them in my car now, it is a 1973 "LA" 318 but uses a big fat short reach spark plug, when I get around to swapping engines in my car I will pull the heads off and see what else is different about them

 

[Timmy's Toy]

Never seen a poly-motor in a motorhome. It's callled a 318-3 (if I remember correctly) It was a industrial use engine. Used extensively for pumps, and forklifts, generators and such. There's a guy that races occasionally here in the Phoenix Metro area that has an old race car hauler, the kind that's enclosed where you drive the car up on an angle in the back. He has a 318-3 in it. (he doesn't go very fast up hills!) I started working in the RV industry in the late 70's and saw a few of those Winnie's come in with the 318's. They were always 318-3's The larger (longer) Winnegago's had 413's in them. The late 70 thru 1980 coaches used 440-3 motor's as well and had different cylinder heads. Again if I remember correctly the heads on the dash-3 motors had big plugs and different shapes because of a an additional cooling jacket around the plugs by the combustion chamber. Normal passenger car and light truck engines were considered to be dash one engines (ie: 318-1, 413-1, 440-1) The class A motorhomes used the dash three engines with the different heads. (ie: 318-3, 413-3, 440-3). See if you can see the side of the block It should say 318-1 or 318-3.

 

[HotLines]

I know this won't answer your question but do you know why there are straight plug heads and angle plug heads?

Angle plug heads use domed pistons, and so
Angle plug heads are alleged to promote better flame propagation over a domed piston because the flame or spark wraps around the dome of the piston.

Straight plug heads use flat top pistons and so
With the straight plug heads, the spark sprays a wide flame or spark across so they work fine with a flat top piston.

The small block Chevy has both angle and straight plug heads, but both these are used in many race applications with the pistons mentioned above.

 

[fishy68]

Never seen a poly-motor in a motorhome. It's callled a 318-3 (if I remember correctly) It was a industrial use engine. Used extensively for pumps, and forklifts, generators and such. There's a guy that races occasionally here in the Phoenix Metro area that has an old race car hauler, the kind that's enclosed where you drive the car up on an angle in the back. He has a 318-3 in it. (he doesn't go very fast up hills!) I started working in the RV industry in the late 70's and saw a few of those Winnie's come in with the 318's. They were always 318-3's The larger (longer) Winnegago's had 413's in them. The late 70 thru 1980 coaches used 440-3 motor's as well and had different cylinder heads. Again if I remember correctly the heads on the dash-3 motors had big plugs and different shapes because of a an additional cooling jacket around the plugs by the combustion chamber. Normal passenger car and light truck engines were considered to be dash one engines (ie: 318-1, 413-1, 440-1) The class A motorhomes used the dash three engines with the different heads. (ie: 318-3, 413-3, 440-3). See if you can see the side of the block It should say 318-1 or 318-3.

Interesting information there. I used to be a mobile mechanic for Hyster forklifts and had a customer with a lift that used the 318 Poly. I have seen the 440's you mentioned that had different heads that had water ports going into the front but the heads on the forklift I worked on used regular car style heads. I always wondered if it had been changed out though since it was so old. I never knew about the -1 vs. -3 signification or I would have looked.

 

[Timmy's Toy]

Interesting information there. I used to be a mobile mechanic for Hyster forklifts and had a customer with a lift that used the 318 Poly. I have seen the 440's you mentioned that had different heads that had water ports going into the front but the heads on the forklift I worked on used regular car style heads. I always wondered if it had been changed out though since it was so old. I never knew about the -1 vs. -3 signification or I would have looked.

It would be rare to see any dash-3 motors today. They were only used in M-series motorhomes (M400, M500, or M600 chassis)or industrial use, at least to my knowledge. M-series motorhomes were the Class A's, the big ones like Winnebago's and such. Mini-motorhomes with the van nose (like the Minnie-Winnie) used the dash-1 engines. The big Class A's from the early to mid-70's used 413-3 motors. They were most different from the 413's of the early 60's. Huge skirted pistons and very heavy rods. Very stout though. It's my understanding that they were used in medium duty trucks up until the mid-70's when Chrysler Corp. decided to get out of the 400, 500, and 600 series truck business. The M-series motorhomes were the last of the medium duty series and they died in 1980.