V/P 454 (7.4l) Quick Engine Question

[Chef Shawn]

My sister-in-law wants to give me a 28ft Harbor Grand with a 7.4 L Volvo motor, for dirt cheap. She says her husband can't fix it and the marina will only offer her $500. She says marina claims the block is cracked (although THEY were in charge of winterizing) . I know NOTHING about this type of motor. It cranks fine and runs for a few seconds before shutting down. The brother-in-law somehow thought to replace the carb when he saw water in the oil. Are these big blocks prone to cracking ( I know all of them can)?

I plan on doing a compression test before I advance. The boat is pristine, but with a shot big block, I don't know if it is worth my time (or money). I don't even know (but guessing) it is a closed cooling system, can I do a leak-down test on it?

Any advice would be helpful.

 

[jerryjerry05]

Re: V/P 454 (7.4l) Quick Engine Question

The drive is worth at least that much.
Need the model and serial # year.
If they didn't winterize it then THEY are responsible for buying and replacing.
Depending on the model, the prop or props could cost a $1000
Pics of the boat,drive.

 

[tpenfield]

Re: V/P 454 (7.4l) Quick Engine Question

Info does not add up . . . if it is a closed cooling system, usually their is anti-freeze coolant in the system . . . so maybe verify all of that stuff.

7.4L marine engines, and 7.4l's in general, are getting scarce as they are no longer built by GM (at least not in any significant quantities) So, many of the available 7.4 engines are remanufactured, and those can be a crap shoot in terms of longevity, etc.

I was faced with having to replace a 7.4 engine last year, and it was looking like $3-4K for re-manufactured and $6K for a new long block. then I would have to transfer all the components from my old engine to the new long block.

Post us some pictures and maybe that will help see what you got.

I would definitely run a cooling system leak test, if you can and maybe do a cylinder leak test as well. That would give you some info on the engine's health. Check for water in the oil, etc.

 

[Chef Shawn]

Re: V/P 454 (7.4l) Quick Engine Question

Thanks guys,

Going up Monday and checking this thing out. Like I said, I don't know jack about this engine, only what those two clowns told me about it(brother and sister-in-law), lol. Will get some pics and #'s. They said it has a good battery so I should be able to check compression.

Now for a WILD CRAZY QUESTION!!!!!
Of course, no trailer in this deal, and it's about 65 miles (land) away. I'm guessing a pretty penny to truck to me. ASSUMING everything checks out and it's worth the $500...here it comes....would towing it with my 17' Chris Craft (140 Mercruiser) 35 miles (water) be an option? Towed plenty of peeps into shore when they broke down, but nothing TWICE my size, lol.

I know I'm gonna get so much crap for even asking...........but hey....

 

[dypcdiver]

Re: V/P 454 (7.4l) Quick Engine Question

Tow it, but take plenty of fuel, you will be amazed how much extra towing takes. Get a good weather forecast for the next at least 6 hours and a couple of tow ropes, and when in open water put at least 100ft of line out. Out drive leg at its highest or remove the prop/s.
Plenty of sun tan cream and enjoy.

 

[Chef Shawn]

Re: V/P 454 (7.4l) Quick Engine Question

Well, of course not quite what I was expecting. Outdrive is pretty scaly, more than I thought possible from Lake Michigan. Couldn't perform a compression test, no water on-site and since my dingle-berry brother-in-law swapped out the carbs to "fix" his problem, he thru the old carb back on and I couldn't find the metal inlet lines, he has it re-routed with a single line that went into the new carb.

Got serial number off engine, couldn't find jack on the drive.

Here's a couple of odd things:
1. Supposed to have a cracked block...could not find any evidence of water inside the engine. I pumped oil from the bottom of the pan, checked dipstick and pulled valve cover to check for water, rust, foaming, etc. Nothing. (the 'guy') that stores the boat says the block is cracked, he did a compression test and my in-laws should just 'sign it over to him')

2. Drive cables move freely.

3. In-laws say boat will fire up, idle rough and then start "blowing water all over the engine compartment" once underway.

4. In-law says he winterized it because he couldn't afford the marina prices, but is vague on HOW HE DID IT.

5. A little over 600 hours on the motor according to the meter.

6. 1989 28ft Harbor Grand, Volvo Penta 7.4L, Volvo Penta Outdrive (could not find numbers, not sure where to look under the scales)