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1981 Caprice Classic Deisel Summer Starting Issues

Thanks for all the support and help you have provided in the past....Also thank to each and every one of you who have answered my not so smart questions during the last year. I am back with some more un-smart question. Last year I have put new(used) diesel 5.7 in my Caprice and got it running...I took couple of 100 mile one way trips and drove around town for the most part. It always smoke in the beginning and took long time to start. I already replaced the erg valve, diesel filter and glow plugs, air filter and have used lucus additive for the. I did not took any chance driving this car in the winters of Minnesota. I have notice last year it did not have enough power for uphill climbing also. Now my question part what can I do to make the start cycle normal or couple try. also how to increase the power in it. also how to make it summer worthy after 6 months of garage


This message has been edited. Last edited by: Caprice_Classic_Diesel_1,

Registered: March 25, 2011Reply With QuoteReport This Post
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Yank that 5.7 and put in a 6.5. I was at the bone yard the other day and there was a 95 Chevy box van with a NA 6.5 that still ran. In the junk yard because the body rusted right off the frame!
Engine and trans will bolt right into the Caprice.

Blessings. Joe 1999 Chevy Suburban w/new optimizer 6500 TD and 1995 Chevy Cube van 6.5L.
Location: Sterling Hts. Michigan USA | Registered: October 18, 2001Reply With QuoteReport This Post
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The hard starting sounds like you still have glow plug issues. Are they getting power? Are the glow plugs good? A malfunctioning controller will take out the new plugs the first time depending on what glow plugs you installed.

I only use the 60G AC glow plugs. They will not burn out if the controller malfunctions. On some of my diesels, I've bypassed the control system and use a high amperage switch to energize the glow plugs (5 to 10 seconds works good).

The low power is normal for a naturally aspirated diesel like the Olds 350. There is a way to turn the fuel up to increase power but it may cause black smoke and high exhaust temps under full power. Also, as the timing chain stretches from mileage, the injector pump timing retards, taking some power and effeciency with it.

Unless you are a good mechanic, converting to a 6.2/6.5 GM diesel will be a big project. And that '96 van mentioned will have an electronic automatic trqaansmission needing some way to control it too.

And on the eigth day the LORD created the turbocharger
Location: Watertown, NY/Ocala, FL | Registered: August 14, 2002Reply With QuoteReport This Post
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Power problem could be any number of things. As Turbobill and JoeM indicated, the 5.7 was no powerhouse but I have driven over 1/2 million miles in cars equipped with this engine and, as long as its not towing anything, you should not have any problem negotiating hills. Lets face it, the 300TD Mercedes is roughly the same power and it was used in many varients many of which tipped the scales higher than the Caprice. They didn't have hill problems.

The problem may be in the fuel lift pump, the fuel filter or in the IP itself. The DB2 IP used in these engines are quite capable of pulling fuel out of the tank without the lift pump untill its at the higher power settings and which point you end up starving the pump. This is usually accompanied by a slight surge from the engine and a general lack of power. In other words, even if you lose a lift pump, the engine will get you home.

I know you replaced the fuel filter when you did the engine swap but with the age of everything, you may well of had a pile of junk in the fuel tank. This would plug up even a new filter in a hurry and again cause fuel starvation. Even running properly I change out the filters twice a year just on spec.

A failing DB2 will also give you the same symptoms. They rarely just quit working but rather just peter out over a period of 500 to 1,000 miles until you can barely make headway. In the early stages hard starting is an issue. More than once I have driven into the driveway with my foot flat on the floor at 20 MPH. Usually caused by a plugged filter but that is also how the pump goes south.

Before you sentence the pump to a life in the bone yard, give the whole system a triple dose of "Stanadyne Fuel Additive". Take that bottle of Lucas and launch it as far away from your car as possible. The only thing that stuff is good for is lubricating your kids bicycle chain. Don't know what Stanadyne put in their formualation but it works. If the lift pump is working properly, the filter is clean and you have no leaks in the fuel system, and the pump still acts up with the Stanadyne than its new IP time.

Let us know how you make out.

The glowplug controller on these engines were a problem. I just wired a Ford starter realy to a momentary on switch on the dash board, installed a set of 60Gs or 11Gs and used 5-10 seconds in the summer and 10-15 seconds in the winter.


91 Buick Roadmaster wagon, GM 6.2 diesel conversion (gone but not forgotten
89 GMC 6.2 (Just got rid of the last pieces)
84 Mercedes 300D (gone to the great autobahn in the sky)
94 Cadillac Fleetwood (Sold before I could convert it)
Location: Manotick, Ontario Canada | Registered: July 02, 2002Reply With QuoteReport This Post
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Im looking to convert my Volvo 740 to a V8 was looking for a 305/350 not looking for any real power.

so got the idea why not go diesel.
i have been thinking about the 6.2 but i might be a little overkill in size for the little volvo so what else? came to think of the olds 350 5.7 diesel..
Registered: March 31, 2012Reply With QuoteReport This Post
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